Mathematical Operations Quiz

In each of the number-pairs, the second number is obtained by performing a certain mathematical operation on the first number. Three of the following pairs follow the same pattern and thus form a group. Select the number-pair that does NOT belong to that group.

• 21: 420

• 15: 208

• 17: 272

• 25: 600

Answer explanation

In the pairs, the second number is typically the first number multiplied by a factor. For example, 21:420 (21x20), 17:272 (17x16), and 25:600 (25x24) follow this pattern. However, 15:208 does not fit as 15x13.87 is not an integer.

The second number in each of the number-pairs is obtained by performing certain mathematical operation on the first number. Three of the following four number-pairs follows the same pattern and thus form a group. Select the number-pairs that do NOT belong to that group.

• 18: 321

• 21: 438

• 19: 357

• 17: 286

Answer explanation

In the pairs, the second number is derived from the first by a consistent operation. For 19: 357, the operation does not match the others, as it does not follow the same pattern of transformation as the other pairs.

In each of the number-pairs, the second number is obtained by performing a certain mathematical operation on the first number. Three of the following pairs follow the same pattern and thus form a group. Select the number-pair that does NOT belong to that group.

• 14: 198

• 18: 325

• 22: 485

• 20: 401

Answer explanation

In the pairs, the second number is derived from the first by a specific operation. For 14:198, the operation does not match the others, which involve a consistent pattern of multiplication and addition. Thus, 14:198 is the odd one out.

In each of the number-pair, the second number is obtained by performing certain mathematical operation on the first number. Three of the following pairs follow the same pattern and thus form a group. Select the number-pair that does NOT belong to that group.

• 22: 133

• 14: 85

• 16: 97

• 18: 107

Answer explanation

In the pairs, the second number is derived by multiplying the first number by 6 and adding 1. For example, 22: 133 (22*6+1), 14: 85 (14*6+1), and 16: 97 (16*6+1) follow this pattern. However, 18: 107 does not fit as 18*6+1 equals 109.

The second number in each of the number-pairs is obtained by performing certain mathematical operations on the first number. Three of the following four number-pairs follow pattern and thus form a group. Select the number-pair that does NOT belong to that group.

• 14: 197

• 19: 363

• 17: 290

• 13: 170

Answer explanation

The pair 19: 363 does not follow the pattern of the others. For the other pairs, the second number is derived from a consistent mathematical operation on the first number, while 19: 363 does not fit this rule.

In the following number-pairs the second number is obtained by applying certain mathematical operations to the first number. In three of the four pairs the same pattern is applied and hence they form a group. Select the number-pair that does NOT belong to this group.

• 24: 590

• 19: 375

• 17: 303

• 8: 82

Answer explanation

In the pairs, the second number is derived from the first by a consistent pattern. For 24:590, 19:375, and 17:303, the operations involve multiplication and addition. However, 8:82 does not follow this pattern, making it the odd one out.

Choose the number - pair that is different from the other three.

• 0: 6

• 21: 46

• 12: 28

• 5: 14

Answer explanation

The pair 0: 6 is different because the first number is 0, while all other pairs have positive integers. Additionally, 0 is not a product of any positive integers, unlike the others.

Choose the number - pair that is different from the other three.

• 65: 16

• 49: 12

• 62: 15

• 33: 8

Answer explanation

The pair 62: 15 is different because 62 is not a perfect square, while 65 (8^2), 49 (7^2), and 33 (5.74^2) are related to perfect squares or their roots. Thus, 62: 15 stands out as the unique pair.

Four numbers have been given, out of which three are alike in some manner and one is different. Select the odd one number.

• 39

• 35

• 37

• 41

Answer explanation

The numbers 39, 35, and 37 are all odd numbers that are less than 40, while 41 is the only number that is greater than 40. Therefore, 41 is the odd one out.

Four number-pairs have been given, out of which three are alike in some manner and one is different. Select the number-pair that is different from the rest.

• 11: 13

• 17: 19

• 12: 15

• 21: 23

Answer explanation

The pairs 11:13, 17:19, and 21:23 consist of consecutive prime numbers, while 12:15 are not prime and are not consecutive primes. Thus, 12:15 is the odd one out.