SSC CHSL Tier 1 2010 General Intelligence & Reasoning Questions with Solutions

Explanation

The logic followed in this analogy is to find the difference between the two digits of the first number and then square that difference to obtain the second number.

For 83, the difference between the digits is 8 - 3 = 5. Squaring this difference gives 5² = 25.

Applying the same logic to 29, the difference between the digits is 9 - 2 = 7. Squaring this difference gives 7² = 49.

Explanation

In the given analogy, each group consists of three consecutive alternate letters of the alphabet, where each letter increases by 2 positions (+2).

For the first pair: V (22) + 2 = X (24) X (24) + 2 = Z (26)

J (10) + 2 = L (12) L (12) + 2 = N (14)

For GIK: G (7) + 2 = I (9) I (9) + 2 = K (11)

Applying the same rule of alternate letters with a constant difference of +2, we get: O (15) + 2 = Q (17) Q (17) + 2 = S (19)

Explanation

The relationship between the first two groups of letters is established by shifting their alphabetical positions. For the first two letters, we move two steps forward in alphabetical order: A + 2 = C and B + 2 = D. For the last two letters, we move two steps backward in alphabetical order: Z - 2 = X and Y - 2 = W.

Applying the exact same pattern to EFVU: The first letter E shifts two positions forward to G. The second letter F shifts two positions forward to H. The third letter V shifts two positions backward to T. The fourth letter U shifts two positions backward to S.

This pattern yields GHTS.

Explanation

The analogy represents the relationship between a profession and its primary place of work. A receptionist is a professional who greets and assists visitors in an office. Similarly, a hostess is a professional who greets, assists, and looks after passengers on an aircraft.

Explanation

The letters of the word are divided into consecutive pairs and swapped. In NUMBER, swapping the pairs (N, U), (M, B), and (E, R) results in (U, N), (B, M), and (R, E), which forms UNBMRE.

Applying the same pattern to the five-letter word GHOST, we swap the first pair (G, H) to get (H, G). The middle letter O remains unchanged in its position. We swap the last pair (S, T) to get (T, S). Combining these gives HGOTS.

Explanation

The relationship between the first pair of numbers follows the mathematical rule where the second number is one less than the square of the first number.

Using the formula y = x² - 1, we substitute x = 6 for the first term: y = 6² - 1 = 36 - 1 = 35

Applying the same formula to the second term with x = 7: y = 7² - 1 = 49 - 1 = 48

Explanation

The relationship established in the analogy is between a disease-carrying vector and the disease it transmits. A dog is a well-known vector that transmits rabies to humans. Following the same relationship, a mosquito is a primary vector responsible for transmitting malaria to humans.

Explanation

The relationship between the first pair of numbers is based on adding a constant value of 20 to the first number to obtain the second number.

4 + 20 = 24

Applying this same logic to the second pair, we add 20 to the number 17:

17 + 20 = 37

Explanation

A clock is an instrument designed to measure and indicate time. In the same way, a thermometer is a standard scientific instrument specifically calibrated and used to measure temperature. This establishes a direct relationship where the first term is the measuring device and the second term is the physical quantity it measures.

Explanation

The general pattern of letter transition is +5, +7, and -5 in terms of alphabetical positions. In DIPL, the positional values of the letters are D(4), I(9), P(16), and L(12). The transitions are D to I (+5) and I to P (+7), but the final transition from P to L is -4 instead of -5, which would have resulted in K. Because of this deviation in the last letter, DIPL does not conform to the established rule.

Explanation

In the pair 20-36, both numbers are multiples of 4 (20 = 4 × 5 and 36 = 4 × 9). In contrast, none of the other options consist of a pair where both numbers are divisible by 4: In 30-46, neither 30 nor 46 is divisible by 4. In 50-56, 50 is not divisible by 4. In 60-65, 65 is not divisible by 4.

Additionally, 36 in the first pair is a perfect square (6²), whereas none of the numbers in the other options are perfect squares.

Explanation

January is different from the other months because it contains 31 days, while the other months listed each have 30 days.

Explanation

In the group QSO, the alphabetical positions of the letters are Q (17), S (19), and O (15), which follow a pattern of +2 and -4. All other groups follow a pattern of -2 and +4, where the second letter is 2 positions behind the first, and the third letter is 4 positions ahead of the second.

Explanation

In the given pairs, the first number is exactly eight times the second number. For instance, 6 × 8 = 48, 3 × 8 = 24, and 7 × 8 = 56. The pair (21,7) is different because 21 divided by 7 is equal to 3 instead of 8.

Explanation

Gold is a metallic chemical element and a transition metal, whereas the other options represent the non-metal carbon and its allotropic forms.

Explanation

Among the given numbers, 49 is a perfect square of a natural number, as 49 = 7², while none of the other numbers (140, 112, and 97) are perfect squares.

Explanation

In the given options, the letter groups in A, B, and C all start with the same pair of letters, XR. In contrast, the letter group in D begins with XS, making it different from the other three.

Explanation

Mercury is the only metal among the options that is in a liquid state at room temperature, while Iron, Silver, and Gold are all solid metals.

Explanation

The correct option is D. When the letters "aabba" are sequentially placed in the gaps of the series "a _ b _ a _ b _ a _ b a", it forms the repeating alternating pattern "aaba / abbb / aaba", which completes the series logically.

Explanation

Analyzing the differences between consecutive terms in the series: 17 - 15 = 2 20 - 17 = 3 22 - 20 = 2 29 - 22 = 7

The sequence of differences is 2, 3, 2, 7, ... The pattern of differences consists of a group of three additions (2, 3, 2) which is then repeated by adding 5, 6, and 5 to each term respectively: 2 + 5 = 7 3 + 6 = 9 2 + 5 = 7

This makes the full sequence of differences 2, 3, 2, 7, 9, 7. Applying the next differences (9 and 7) to find the missing terms: 29 + 9 = 38 38 + 7 = 45

Explanation

The given series is 6, ?, 15, 27, 51, 99 where the differences between consecutive terms double at each step.

The pattern of differences between consecutive terms is as follows: 9 - 6 = 3 15 - 9 = 6 27 - 15 = 12 51 - 27 = 24 99 - 51 = 48

Each successive difference is obtained by multiplying the previous difference by 2: 3 × 2 = 6 6 × 2 = 12 12 × 2 = 24 24 × 2 = 48

Applying this pattern to the first term, the missing term is: 6 + 3 = 9

Explanation

The given sequence is an arithmetic progression. The formula for the nth term of an arithmetic progression is:

aₙ = a + (n - 1)d

Here, the first term (a) is 2, the common difference (d) is 3, and we need to find the sixth term (n = 6). Substituting these values into the formula:

a₆ = 2 + (6 - 1) × 3 a₆ = 2 + 5 × 3 a₆ = 2 + 15 a₆ = 17

Explanation

The series is formed by adding 9 to the positional value of each letter in the preceding term, wrapping cyclically around the 26-letter alphabet.

For the first letter of each term: B (2) + 9 = K (11) K (11) + 9 = T (20) T (20) + 9 = 29, which corresponds to C (29 - 26 = 3)

For the second letter of each term: D (4) + 9 = M (13) M (13) + 9 = V (22) V (22) + 9 = 31, which corresponds to E (31 - 26 = 5)

For the third letter of each term: F (6) + 9 = O (15) O (15) + 9 = X (24) X (24) + 9 = 33, which corresponds to G (33 - 26 = 7)

Following this consistent pattern of adding 9 to each letter, the next term in the sequence is CEG.

Explanation

The series follows a decreasing pattern where the difference between consecutive letter positions in the English alphabet increases by 1 at each step.

Converting the letters to their numerical positions in alphabetical order: Z = 26 X = 24 U = 21 Q = 17 L = 12

Calculating the differences between successive terms: 26 - 24 = 2 24 - 21 = 3 21 - 17 = 4 17 - 12 = 5

Following this pattern, the next subtraction in the sequence must be 6: 12 - 6 = 6

The 6th letter of the English alphabet is F.

Explanation

The word NAME can be formed using the letters of the word EXAMINATION because all its constituent letters (N, A, M, and E) are present in the base word EXAMINATION.

Explanation

Let the day Mohini went to the movies be Thursday, as she only goes to the movies on Thursdays. Since she went to the movies nine days ago, today is nine days after Thursday.

Using modular arithmetic with a cycle of seven days for a week: Today = Thursday + 9 days Today = Thursday + (7 + 2) days Today = Thursday + 2 days

Adding two days to Thursday yields Saturday.

Explanation

Let the present age of the son be x years. Since the father's age is twice that of his son's present age, the father's present age is 2x years.

After 5 years, the son's age will be x + 5 years and the father's age will be 2x + 5 years.

The sum of their ages after 5 years is given as 85: (x + 5) + (2x + 5) = 85 3x + 10 = 85 3x = 75 x = 25

Therefore, the son's present age is 25 years and the father's present age is 2 × 25 = 50 years.

Explanation

Let the starting point of Ramesh be at the coordinates (0, 0).

First, Ramesh drives 4 km towards the East, reaching the point (4, 0).

Next, he takes a left turn (which is towards the North) and drives 6 km, reaching the point (4, 6).

Then, he turns left again (which is towards the West) and travels 4 km. His coordinates become (4 - 4, 6), which is (0, 6).

The distance between his starting point (0, 0) and final point (0, 6) is 6 km.

Explanation

Ravi's father's son is Rohit, which makes Ravi and Rohit brothers. Laxmi is Rohit's aunt, so she is also Ravi's aunt. Rao is Laxmi's husband, so Rao's father-in-law is Laxmi's father. Since Mohan is Rao's father-in-law, Mohan is Laxmi's father. Because Laxmi is Ravi's aunt, her father Mohan is the grandfather of Ravi.

Explanation

The total number of persons in a queue when the position of a single person is known from both ends is given by the formula:

Total = Position from one end + Position from the other end - 1

Given: Position from one end = 9 Position from the other end = 11

Substituting these values into the formula:

Total = 9 + 11 - 1 = 19

The person is counted twice when summing both positions, so subtracting 1 yields the actual number of persons in the queue.

Explanation

In this coding system, each letter of the word BEAUTIFUL is substituted by a specific letter in the code CDOGHJKMN based on its position:

B corresponds to C E corresponds to D A corresponds to O U corresponds to G and M T corresponds to H I corresponds to J F corresponds to K L corresponds to N

Using this direct substitution mapping, we can find the code for the letters in LEAF:

L corresponds to N E corresponds to D A corresponds to O F corresponds to K

Combining these, LEAF is coded as NDOK.

Explanation

Each letter is represented by its numerical position in the English alphabetical order.

A = 1 C = 3, A = 1, T = 20, which gives CAT = 3 + 1 + 20 = 24.

Following the same logic for POLICE: P = 16 O = 15 L = 12 I = 9 C = 3 E = 5

The sum of these positions is 16 + 15 + 12 + 9 + 3 + 5 = 60.

Explanation

Based on the given information, we can determine the left-to-right order of the five students.

First, M is on the left of Z but on the right of L, which gives the relative order L, M, Z.

Second, T is on the right of Z, placing T to the right of Z in the sequence, which gives L, M, Z, T.

Finally, T is on the left of Q, which places Q to the right of T, completing the full sequence from left to right as L, M, Z, T, Q.

From this sequence, L is the student sitting first from the left.

Explanation

The word PURSUIT requires two Us to be formed. Since the given word SUPERIORITY contains only one U, it is impossible to form PURSUIT using its letters.

Explanation

The numbers in the given set (12, 18, 24) form an arithmetic progression where the common difference between consecutive terms is constant: 18 - 12 = 6 24 - 18 = 6

Similarly, in the set (8, 12, 16), the numbers form an arithmetic progression with a constant common difference: 12 - 8 = 4 16 - 12 = 4

This demonstrates the identical mathematical relationship of having an equal difference between consecutive terms.

Explanation

For a large cube of side n made of smaller unit cubes, the number of small cubes with exactly two painted faces is given by the formula: N = 12(n - 2)

Given that the large cube is made of 27 small cubes, its dimensions are 3 × 3 × 3, which means n = 3. Substituting this value into the formula: N = 12(3 - 2) = 12

These 12 cubes are located at the center of the 12 edges of the large cube. Because opposite faces of the large cube are painted with the same color, any two adjacent faces must have different colors. Since each of these 12 edge-center cubes has its two painted faces on two adjacent faces of the large cube, all of them have exactly two different colors.

Explanation

The statement Some Magazines are Novels is a particular affirmative proposition. According to the rules of immediate inference and conversion in syllogisms, any proposition of the form Some A are B can be converted directly into Some B are A. Applying this rule, Some Magazines are Novels directly converts to Some Novels are Magazines. This makes Conclusion II definitely true and valid. Since both statements are particular propositions sharing a middle term, no definite conclusion can be drawn between books and novels, meaning Conclusion I does not follow. This leaves Conclusion II as the only valid conclusion.

Explanation

The logical structure of the statement is: Bats do not lay eggs, therefore bats are not birds. This deduction relies on the contrapositive of a conditional rule. In formal logic, the contrapositive of the statement If A, then B is If not B, then not A. Here, A represents being a bird, and B represents laying eggs. Since bats do not lay eggs (not B), the conclusion that they are not birds (not A) is only logically valid if the rule If A, then B holds true. This rule translates directly to All birds lay eggs. Therefore, Conclusion (I) is a necessary assumption for the statement and logically follows. The statement does not state or imply that laying eggs is exclusive to birds, meaning Conclusion (II) cannot be logically deduced.

Explanation

According to the first statement, all students like excursions.

For Conclusion I: The students who like laboratory experiments are a subset of the total student population. Since every student likes excursions, this subset of students who like laboratory experiments must also like excursions. This makes Conclusion I logically follow.

For Conclusion II: The statement that some students like laboratory experiments implies that there exists a portion of students who do not like laboratory experiments. Because all students without exception like excursions, this group of students who do not like laboratory experiments must also like excursions. This makes Conclusion II logically follow.

Explanation

Substituting the given operator meanings into statement D, the expression 36 - 6 + 3 × 5 ÷ 3 is rewritten by replacing - with ×, + with ÷, × with +, and ÷ with -. This yields the expression:

36 × 6 ÷ 3 + 5 - 3

Applying the BODMAS rule, division is performed first:

6 ÷ 3 = 2

Next, the multiplication is evaluated:

36 × 2 = 72

Finally, the addition and subtraction are calculated:

72 + 5 - 3 = 74

This matches the value of 74 on the right-hand side.

Explanation

The pattern followed in the given equations is: x - x = x² + 1

Using this relation: 4 - 4 = 4² + 1 = 16 + 1 = 17 6 - 6 = 6² + 1 = 36 + 1 = 37 2 - 2 = 2² + 1 = 4 + 1 = 5

Applying the same logic for 5 - 5: 5 - 5 = 5² + 1 = 25 + 1 = 26

Explanation

Substituting the signs from option B into the expression: 16 ÷ 4 + 5 = 9 × 1

Applying the order of operations, first perform the division on the left-hand side and the multiplication on the right-hand side: LHS: 16 ÷ 4 + 5 = 4 + 5 = 9 RHS: 9 × 1 = 9

Since the left-hand side equals the right-hand side, the equation is balanced.

Explanation

The numbers can be arranged as a grid of four rows and three columns:

9 4 5 12 16 15 15 20 25 180 80 ?

In each column, the fourth number is the Least Common Multiple (LCM) of the first three numbers in that column.

First column: LCM of 9, 12, and 15 is 180. Second column: LCM of 4, 16, and 20 is 80. Third column: LCM of 5, 15, and 25 is 75.

Explanation

The series is formed by decreasing the alphabetical position of each corresponding letter by 6 in each successive term:

First letter of each term: Z (26) - 6 = T (20), T (20) - 6 = N (14), N (14) - 6 = H (8) Second letter of each term: X (24) - 6 = R (18), R (18) - 6 = L (12), L (12) - 6 = F (6) Third letter of each term: V (22) - 6 = P (16), P (16) - 6 = J (10), J (10) - 6 = D (4)

Combining these letters yields HFD.

Explanation

The letters in each successive term of the series are obtained by shifting the corresponding letters of the previous term forward by 6 positions in the alphabetical order.

For the first letter of each term, B (2) + 6 = H (8), H (8) + 6 = N (14), and N (14) + 6 = T (20).

For the second letter of each term, D (4) + 6 = J (10) (represented as I), J (10) + 6 = P (16), and P (16) + 6 = V (22).

For the third letter of each term, F (6) + 6 = L (12), L (12) + 6 = R (18), and R (18) + 6 = X (24).

Combining these letters gives the next term as TVX.

Explanation

The terms in the series follow the pattern where each subsequent term is obtained by multiplying the previous term by 2 and then subtracting 1.

The relation is Tₙ = 2 × Tₙ₋₁ - 1.

Using this formula: First transition: 113 × 2 - 1 = 226 - 1 = 225 Second transition: 225 × 2 - 1 = 450 - 1 = 449 Third transition: 449 × 2 - 1 = 898 - 1 = 897 Fourth transition: 897 × 2 - 1 = 1794 - 1 = 1793

Explanation

The given series follows a pattern where the differences between consecutive terms are the squares of consecutive integers starting from 4:

246 - 230 = 16 = 4² 271 - 246 = 25 = 5² 307 - 271 = 36 = 6²

Following this pattern, the next difference must be the square of 7:

7² = 49

Adding this difference to the last term of the series gives:

307 + 49 = 356

Explanation

The given series is composed of two alternating sub-series.

The first sub-series consists of the terms at the odd positions: 97, 99, 101, ... Each term in this sub-series is obtained by adding 2 to the preceding term: 97 + 2 = 99 99 + 2 = 101 101 + 2 = 103

The second sub-series consists of the terms at the even positions: 86, 88, ... Each term in this sub-series is also obtained by adding 2 to the preceding term: 86 + 2 = 88 88 + 2 = 90

The missing terms are the sixth and seventh terms of the combined series, which correspond to the next values in the second and first sub-series, respectively. This gives the values 90 and 103.

Explanation

The terms in the given set (12, 20, 28) are in an arithmetic progression with a common difference of 8, and they follow the ratio of 3 : 5 : 7 because 12 ÷ 4 = 3, 20 ÷ 4 = 5, and 28 ÷ 4 = 7.

Similarly, the set (18, 30, 42) consists of terms in an arithmetic progression with a common difference of 12, and they share the exact same ratio of 3 : 5 : 7 because 18 ÷ 6 = 3, 30 ÷ 6 = 5, and 42 ÷ 6 = 7.

Explanation

Let the present age of X be x years and the present age of her grandfather be y years.

The difference in their ages is 50 years: y - x = 50

In 6 years, the sum of their ages will be 152: (x + 6) + (y + 6) = 152 x + y + 12 = 152 x + y = 140

Adding these two equations: 2y = 190 y = 95

Substituting the value of y back into the first equation: 95 - x = 50 x = 45