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
7071
If 5 years are added to A's age, it becomes equal to B's age 5 years ago. If A is 10 years old, what is B's present age?
Answer:
20
A + 5 = B - 5. Since A = 10, 15 = B - 5 => B = 20.
7072
The ratio of the ages of A and B is 5:2. If the product of their ages is 160, what is the age of A?
Answer:
20
Ages 5x, 2x. Product = 10x^2 = 160 => x^2 = 16 => x = 4. A = 5(4) = 20.
7073
A mother's age is 4 times her daughter's age. 10 years from now, the mother's age will be twice the daughter's age. Find the daughter's present age.
Answer:
5
M = 4D. M + 10 = 2(D + 10) => 4D + 10 = 2D + 20 => 2D = 10 => D = 5.
7074
The ratio of A's age to B's age is 2:3. If A's age increases by 4 years and B's age increases by 4 years, the ratio becomes 3:4. What is A's present age?
Answer:
8
Ages 2x, 3x. (2x + 4)/(3x + 4) = 3/4 => 8x + 16 = 9x + 12 => x = 4. A = 2(4) = 8.
7075
A father's age is 3 times his son's age. After 12 years, he will be twice as old as his son. What is the son's present age?
Answer:
12
F = 3S. F + 12 = 2(S + 12) => 3S + 12 = 2S + 24 => S = 12.
7076
The average age of 5 boys is 12 years. If the age of one more boy is added, the average becomes 13 years. What is the age of the new boy?
Answer:
18
Sum of 5 boys = 60. Sum of 6 boys = 78. New boy = 78 - 60 = 18.
7077
In 12 years, a man will be 3 times as old as he was 12 years ago. Find his present age.
Answer:
24
M + 12 = 3(M - 12) => M + 12 = 3M - 36 => 2M = 48 => M = 24.
7078
The ratio of the ages of A and B is 5:6. If B is 6 years older than A, what is the sum of their ages?
Answer:
66
Difference = 1 part = 6. Sum = 11 parts = 11 * 6 = 66.
7079
If 3 times A's age is equal to 4 times B's age, and the sum of their ages is 35, what is A's age?
Answer:
20
3A = 4B => A:B = 4:3. Sum = 7 parts = 35 => 1 part = 5. A = 4 parts = 20.
7080
The sum of ages of a brother and sister is 30. Five years ago, the brother was 3 times as old as the sister. Find the sister's present age.
Answer:
10
B + S = 30. B - 5 = 3(S - 5) => 25 - S = 3S - 15 => 4S = 40 => S = 10.