Arithmetic Aptitude 3

Question 1

Present age of Vinod and Ashok are in ratio of 3:4 respectively. After 5 years, the ratio of their ages becomes 7:9 respectively. What is Ashok’s present age is ?

• A. 40 years
• B. 28 years
• C. 32 years
• D. 36 years

Answer: (A)

Arithmetic Aptitude 3 Ratio and Proportion Age 50 Aptitude & Reasoning MCQs with Answers
Discuss it

Let the present age of Vinod and Ashok be 3x years and 4x years respectively.

Then (3x+5) / (4x+5)  = 7 / 9 

∴ 9(3x + 5) = 7(4x + 5)
∴ 27x + 45 = 28x + 35
∴ x = 10
∴ Ashok’s present age = 4x = 40 years 

Question 2

At present, the ratio between ages of Ram and Shyam is 6:5 respectively. After 7 years, Shyam’s age will be 32 years. What is the present age of Ram?

• A. 32
• B. 40
• C. 30
• D. 36

Answer: (C)

Arithmetic Aptitude 3 Ratio and Proportion Age 50 Aptitude & Reasoning MCQs with Answers
Discuss it

Let the present age of Ram and Shyam be 6x years and 5x years respectively.

Then 5x + 7 = 32
∴      5x = 25
∴        x = 5
∴ Present age of Ram = 6x = 30 years

Question 3

The present ages of A, B and C are in proportions 4:5:9. Nine years ago, sum of their ages was 45 years. Find their present ages in years

• A. 15,20,35
• B. 20,24,36
• C. 20,25,45
• D. 16,20,36

Answer: (D)

Arithmetic Aptitude 3 Age Ratio and Proportion 50 Aptitude & Reasoning MCQs with Answers
Discuss it

Let the current ages of A, B and C be ax years, 5x years and 9x respectively.

Then (4x-9) + (5x-9) + (9x-9) =45
∴ 18x – 27 = 45
∴ 18x = 72
∴ x = 4

Present ages of A, B and C are 4x = 16, 5x = 20, 9x = 36 respectively.

Question 4

A person’s present age is one third of the age of his mother. After 12 years, his age will be one half of the age of his mother. What is present age of his mother?

• A. 30
• B. 34
• C. 38
• D. 36

Answer: (D)

Arithmetic Aptitude 3 Age
Discuss it

Le the present ages of son and his mother are x years and 3x years.

Then (3x + 12) = 2( x + 12)
∴ 3x + 12 = 2x + 24
∴ x = 12
∴ Present age of mother = 3x = 36 years 

Question 5

A is as older than B as he is younger than C.If the sum of ages of B and C is 68 years. What is the present age of A?

• A. 24 years
• B. 34 years
• C. 28 years
• D. 32 years

Answer: (B)

Arithmetic Aptitude 3 Age 50 Aptitude & Reasoning MCQs with Answers
Discuss it

A – B = C – A
∴ 2A = B + C
And also given that B + C = 68
∴ 2A = 68
∴   A = 34 

Question 6

Opportunistic reasoning is addressed by which of the following knowledge representation

• A. Script
• B. Blackboard
• C. Production Rules
• D. Fuzzy Logic

Answer: (B)

ISRO CS 2013 Arithmetic Aptitude 3 50 Aptitude & Reasoning MCQs with Answers
Discuss it

Opportunistic reasoning is a method of selecting suitable logical inference strategy from the knowledge base of the AI system. Blackboard is an AI model of opportunistic reasoning where a common knowledge base is updated frequently by diverse knowledge sources. So, (B) is the correct option.