Arithmetic Aptitude 4

Question 1

Raghav has got a bag of numbers from 1 to 500, however he want to remove the numbers those are multiple of 9. How many total numbers will be removed?

• A. 44
• B. 55
• C. 50
• D. 52

Answer: (B)

Arithmetic Aptitude 4 Number Divisibility
Discuss it

The required numbers are 9, 18, 27, 36, 45……450, 459, 468, 477, 486, 495

This is an A.P. with a = 9 and d = 9

Let it has n terms.

Then Tn = 495 = 9 + (n-1) x9

∴ 495 = 9 + 9n - 9

∴ 9n = 495

∴ n = 55

Question 2

How many terms are there in 3,9,27,81........531441?

• A. 25
• B. 12
• C. 13
• D. 14

Answer: (B)

Arithmetic Aptitude 4 Numbers 50 Aptitude & Reasoning MCQs with Answers
Discuss it

3, 9, 27, 81..............531441 form a G.P. 
with a = 3 and r = 9/3 = 3
Let the number of terms be n

According to the formula, N^th term of the G.P is represented as T_n = a x r^n-1

Then 3 x 3n-1 = 531441
∴ 3n = 312
∴ n = 12

Question 3

7 + 7² + 7³...........7⁶ =?

• A. 140136
• B. 142156
• C. 133256
• D. 137256

Answer: (D)

Arithmetic Aptitude 4 Simplification and Approximation 50 Aptitude & Reasoning MCQs with Answers
Discuss it

Given series is a G. P. with a = 7, r = 7 and n = 6

∴ Sn = a(rn-1) / (r-1)

∴ Sn = 7(76-1) / 6

  Sn = = 137256

Question 4

Two numbers are in the ratio of 2:9. If their H. C. F. is 19, numbers are:

• A. 6, 27
• B. 8, 36
• C. 38, 171
• D. 20, 90

Answer: (C)

Arithmetic Aptitude 4 Ratio and Proportion HCF
Discuss it

Let the numbers be 2X and 9X
Then their H.C.F. is X, so X = 19
∴ Numbers are (2x19 and 9x19) i.e. 38 and 171

Question 5

Subhash has 90 currency notes, some of which are Rs. 1000 denomination and rest of Rs. 500 denomination. The total amount is Rs 71,000. How many notes he has in denomination of Rs. 500?

• A. 30
• B. 32
• C. 34
• D. 38

Answer: (D)

Arithmetic Aptitude 4 50 Aptitude & Reasoning MCQs with Answers
Discuss it

Let the no. of Rs. 500 note be X
Then the no. of Rs. 1000 note = 90 – X
∴ 500X + 1000(90 – X) = 71000
∴ 500X + 90000 – 1000X = 71000
∴ 500X = 19000
∴ X = 38

Question 6

If the average of four consecutive odd numbers is 16, find the smallest of these numbers?

• A. 5
• B. 7
• C. 13
• D. 11

Answer: (C)

Arithmetic Aptitude 4 Numbers 50 Aptitude & Reasoning MCQs with Answers
Discuss it

Let the numbers be x, x+2, x+4 and x+6
Then (x + x + 2 + x + 4 + x + 6)/4  = 16
∴ 4x + 12 = 64
∴ x = 13

Question 7

If the sum of two numbers is 13 and the sum of their square is 85. Find the numbers?

• A. 6 & 7
• B. 5 & 8
• C. 4 & 9
• D. 3 & 10

Answer: (A)

Arithmetic Aptitude 4 Numbers 50 Aptitude & Reasoning MCQs with Answers
Discuss it

Let the numbers be x and 13-x Then x² + (13 – x)² = 85 ∴ x² + 169 + x² – 26x = 85 ∴ 2 x² – 26x + 84 = 0 ∴ x² – 13x + 42 = 0 ∴ (x-6)(x-7)=0 Hence numbers are 6 & 7