All Categories MCQs
Topic Notes: All Categories
General Description
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
7111
A is as much younger than B as he is older than C. If the sum of the ages of B and C is 48 years, what is the present age of A?
Answer:
24
B - A = A - C => B + C = 2A. 48 = 2A => A = 24.
7112
Three years ago, the sum of the ages of a father and his son was 40 years. After 2 years, the sum of their ages will be:
Answer:
50
Sum 3 years ago = 40. Present sum = 40 + (2 * 3) = 46. Sum after 2 years = 46 + (2 * 2) = 50.
7113
The present age of a father is 5 times the age of his son. Five years ago, the age of the father was 10 times the age of his son. Find the present age of the son.
Answer:
9
F = 5S. F - 5 = 10(S - 5). 5S - 5 = 10S - 50 => 5S = 45 => S = 9.
7114
Hitesh is 40 years old and Rohit is 60 years old. How many years ago was the ratio of their ages 3 : 5?
Answer:
10 years
Let it be x years ago. (40 - x) / (60 - x) = 3 / 5 => 200 - 5x = 180 - 3x => 2x = 20 => x = 10.
7115
The ages of A and B are in the ratio 6 : 5 and the sum of their ages is 44 years. What will be the ratio of their ages after 8 years?
Answer:
8 : 7
Total parts = 11. 11 parts = 44 => 1 part = 4. Ages are 24 and 20. After 8 years: 32 and 28. Ratio = 32 : 28 = 8 : 7.
7116
If the sum of the ages of A and B is 60 and the ratio of their ages is 2 : 3, what is the age of A?
Answer:
24
Total parts = 5. 5 parts = 60 => 1 part = 12. A = 2 parts = 24.
7117
A mother is twice as old as her son. If 20 years ago, the age of the mother was 10 times the age of the son, what is the present age of the mother?
Answer:
45
M = 2S. 20 years ago: M - 20 = 10(S - 20). Substitute M: 2S - 20 = 10S - 200 => 8S = 180 => S = 22.5. Mother = 45.
7118
Ravi is 15 years younger than his brother. After 5 years, the ratio of their ages will be 2 : 3. What is Ravi's present age?
Answer:
25
Let brother be x. Ravi is x - 15. After 5 years: Ravi = x - 10, Brother = x + 5. (x - 10) / (x + 5) = 2 / 3 => 3x - 30 = 2x + 10 => x = 40. Ravi = 40 - 15 = 25.
7119
The present age of a boy is one-third of his father's age. 15 years hence, he will be half of his father's age. The present age of the boy is:
Answer:
15
B = F/3 => F = 3B. In 15 years: B + 15 = (F + 15)/2. Substitute F: 2(B + 15) = 3B + 15 => 2B + 30 = 3B + 15 => B = 15.
7120
The ratio of the present ages of P and Q is 3 : 4. Five years ago, the ratio of their ages was 5 : 7. Find their present ages.
Answer:
30, 40
Ages 3x, 4x. (3x - 5)/(4x - 5) = 5/7 => 21x - 35 = 20x - 25 => x = 10. Present ages are 30 and 40.