Olympiad Test: Odd One Out -1


20 Questions MCQ Test Science Olympiad Class 7 | Olympiad Test: Odd One Out -1


Description
This mock test of Olympiad Test: Odd One Out -1 for Class 7 helps you for every Class 7 entrance exam. This contains 20 Multiple Choice Questions for Class 7 Olympiad Test: Odd One Out -1 (mcq) to study with solutions a complete question bank. The solved questions answers in this Olympiad Test: Odd One Out -1 quiz give you a good mix of easy questions and tough questions. Class 7 students definitely take this Olympiad Test: Odd One Out -1 exercise for a better result in the exam. You can find other Olympiad Test: Odd One Out -1 extra questions, long questions & short questions for Class 7 on EduRev as well by searching above.
QUESTION: 1

Directions: Find the odd one out.

3, 5, 7, 12, 17, 19

Solution:

Each of the numbers is a prime number except 12.

QUESTION: 2

Directions: Find the odd one out.

41, 43, 47, 53, 61, 71, 73, 81

Solution:

Each of the numbers except 81 is a prime number.

QUESTION: 3

Directions: Find the odd one out.

835, 734, 642, 751, 853, 981, 532

Solution:

In each number except 751, the difference of third and first digit is the middle one.

QUESTION: 4

Directions: Find the odd one out.

331, 482, 551, 263, 383, 362, 284

Solution:

In each number except 383, the product of first and third digits is the middle one.

QUESTION: 5

Directions: Find the odd one out.

16, 25, 36, 72, 144, 196, 225

Solution:

Each of the numbers except 72 is a perfect square.

QUESTION: 6

Directions: Find the odd one out.

2, 5, 10, 17, 26, 37, 50, 64

Solution:

(1 × 1) + 1, (2 × 2) + 1, (3 × 3) +1, (4 × 4) + 1, 
(5 × 5) + 1, (6 × 6) + 1, (7 × 7) + 1, (8 × 8) + 1
But, 64 is out of pattern.

QUESTION: 7

Directions: Find the odd one out.

582, 605, 588, 611, 634, 617, 600

Solution:

Alternatively 23 is added and 17 is subtracted from the terms. So, 634 is wrong.

QUESTION: 8

Directions: Find the odd one out.

56, 72, 90, 110, 132, 150

Solution:

The numbers are 7 x 8, 8 x 9, 9 x 10, 10 x 11, 11 x 12, 12 x 13.
So, 150 is wrong.

QUESTION: 9

Directions: Find the odd one out.

36, 54, 18, 27, 9, 18.5, 4.5

Solution:

The terms are alternatively multiplied by 1.5 and divided by 3. However, 18.5 do not satisfy it.

QUESTION: 10

Directions: Find the odd one out.

6, 13, 18, 25, 30, 37, 40

Solution:

The differences between two successive terms from the beginning are 7, 5, 7, 5, 7, 5.
So, 40 is wrong.

QUESTION: 11

Directions: Find the odd one out.

46080, 3840, 384, 48, 24, 2, 1

Solution:

The terms are successively divided by 12, 10, 8, 6, ...etc.
So, 24 is wrong, it should be 8 (48/6 = 8).

QUESTION: 12

Directions: Find the odd one out.

7, 8, 18, 57, 228, 1165, 6996

Solution:

Let the given numbers be A, B, C, D, E, F, G.
Then, A, A x 1 + 1, B x 2 + 2, C x 3 + 3, D x 4 + 4, E x 5 + 5, F x 6 + 6 are the required numbers.
Clearly, 228 is wrong.

QUESTION: 13

Directions: Find the odd one out.

190, 166, 145, 128, 112, 100, 91

Solution:

Go on subtracting 24, 21, 18, 15, 12, 9 from the numbers to get the next number.
190 – 24 = 166
166 – 21 = 145
145 – 18 = 127 [Here, 128 is placed instead of 127] 127 – 15 = 112
112 – 12 = 100 ... and so on.
Therefore, 128 is wrong.

QUESTION: 14

Directions: Find the odd one out.

445, 221, 109, 46, 25, 11, 4

Solution:

Go on subtracting 3 and dividing the result by 2 to obtain the next number.
Clearly, 46 is wrong.

QUESTION: 15

Directions: Find the odd one out.

196, 169, 144, 121, 100, 80, 64

Solution:

Numbers must be (14)2, (13)2, (12)2, (11)2, (10)2, (9)2, (8)2.
So, 80 is wrong.

QUESTION: 16

Directions: Find the odd one out.

3, 7, 15, 27, 63, 127, 255

Solution:

Go on multiplying the number by 2 and adding 1 to it to get the next number.
So, 27 is wrong.

QUESTION: 17

Directions: Find the odd one out.

2880, 480, 92, 24, 8, 4, 4

Solution:

Go on dividing by 6, 5, 4, 3, 2, 1 respectively to obtain the next number.
Clearly, 92 is wrong.

QUESTION: 18

Directions: Find the odd one out.

10, 26, 74, 218, 654, 1946, 5834

Solution:

2nd term = (1st term) × 3 – 4 = 10 × 3 – 4 = 26 
3rd term = (2nd term) × 3 – 4 = 26 × 3 – 4 = 74 
4th term = (3th term) × 3 – 4 = 74 × 3 – 4 = 218
5th term = (4th term) ×3 – 4 = 218 × 3 – 4 = 650.
5th term must be 650 instead of 654.

QUESTION: 19

Directions: Find the odd one out.

15, 16, 34, 105, 424, 2124, 12576

Solution:

2nd term = (1st term) x 1 + 1 = 15 x 1 + 1 = 16 
3rd term = (2nd term) x 2 + 2 = 16 x 2 + 2 = 34 
4th term = (3th term) x 3 + 3 = 34 x 3 + 3 = 105.
5th term = (4th term) x 4 + 4 = 105 x 4 + 4 = 424 
6th term = (5th term) x 5 + 5 = 424 x 5 + 5 = 2125 
6th term should 2125 instead of 2124.

QUESTION: 20

Directions: Find the odd one out.

64, 71, 80, 91, 104, 119, 135, 155

Solution:

Go on adding 7, 9, 11, 13, 15, 17, 19 respectively to obtain the next number.
So, 135 is wrong.