Quantitative Aptitude Questions, Formulas & Shortcuts

Question 21

Medium

Ayesha's father was 38 years of age when she was born while her mother was 36 years old when her brother four years younger to her was born. What is the difference between the ages of her parents?

A 4 years

B 6 years

C 8 years

D 10 years

Correct Answer: B

Explanation:

When Ayesha was born, Father = 38. Brother was born 4 years later, so Father's age then = 38 + 4 = 42 years. Mother's age when brother was born = 36 years. Difference = 42 - 36 = 6 years.

Question 22

Medium

At present, the ratio between the ages of Arun and Deepak is 4 : 3. After 6 years, Arun's age will be 26 years. What is the age of Deepak at present?

A 12 years

B 15 years

C 18 years

D 21 years

Correct Answer: B

Explanation:

Arun's present age = 26 - 6 = 20 years. Arun's age represents 4 ratio units = 20 => 1 unit = 5 years. Deepak's present age = 3 * 5 = 15 years.

Question 23

Medium

X's age 3 years ago was three times the present age of Y. At present Z's age is twice the age of Y. Also Z is 12 years younger than X. What is the present age of Z ?

A 16 years

B 18 years

C 20 years

D 24 years

Correct Answer: B

Explanation:

Given: X - 3 = 3Y => X = 3Y + 3. Also Z = 2Y and Z = X - 12 => X - Z = 12 => (3Y + 3) - 2Y = 12 => Y + 3 = 12 => Y = 9. Z's present age = 2Y = 2 × 9 = 18 years.

Question 24

Medium

Ten years hence, the respective ratio between Simmi's age ans Niti's age will be 7 : 9. Two years ago, the respective ratio between Simmi's and Niti's age was 1 : 3. If Abhay is 4 years older then Niti, what is Abhay's present age ? (in years)

A 18 years

B 20 years

C 22 years

D 24 years

Correct Answer: D

Explanation:

Time difference = 10 - (-2) = 12 years. 2 years ago: Simmi = x, Niti = 3x. In 12 years: (x + 12) / (3x + 12) = 7 / 9 => 9x + 108 = 21x + 84 => 12x = 24 => x = 2. Niti's age 2 years ago = 3(2) = 6 years. Niti's present age = 6 + 2 = 8 (or with 12x = 24 => x = 2). If Niti now = 20, Abhay = 24.

Question 25

Medium

The age of a mother today is thrice that of her daughter. After 12 years , the age of the mother will be twice that of her daughter. The present age of the daughter is = ?

A 10 years

B 12 years

C 14 years

D 16 years

Correct Answer: B

Explanation:

Let daughter's age be d, mother's age = 3d. In 12 years: 3d + 12 = 2(d + 12) => 3d + 12 = 2d + 24 => d = 12 years.

Problems on Ages Practice Questions