Question Detail

A is three times as old as B. C was twice-as old as A four years ago. In four years' time, A will be 31. What are the present ages of B and C ?

9, 46
9, 50
10, 46
10, 50

Answer: Option B

Explanation:

As from the question we have,
A = 3B --- (i)
c - 4 = 2(A+4) ---(ii)

Also, A + 4 = 31
or A = 31-4 = 27

Putting A = 27 in (i) we get
B = 9
Putting A = 27 in (ii) we get
C = 50

1. A is three times as old as B. C was twice-as old as A four years ago. In four years' time, A will be 31. What are the present ages of B and C ?

9, 46
9, 50
10, 46
10, 50

Answer: Option B

Explanation:

As from the question we have,
A = 3B --- (i)
c - 4 = 2(A+4) ---(ii)

Also, A + 4 = 31
or A = 31-4 = 27

Putting A = 27 in (i) we get
B = 9
Putting A = 27 in (ii) we get
C = 50

2. A group of 1200 persons consisting of captains and soldiers is travelling in a train. For every 15 soldiers there is one captain. The number of captains in the group is ?

Answer: Option B

Explanation:

Generally we may commit mistake of dividing 1200/15.
But out of 16 persons there is one captain.
so, it will be 1200/16 = 75

3. Reena is twice as old as Sunita. Three years ago, she was three times as old as Sunita. How old is Reena now ?

6 years
12 years
14 years
16 years

Answer: Option B

Explanation:

Let Sunita's present age = x years
Then Reena present age = 2x years

Three years ago
(2x-3) = 3(x-3)
2x - 3 = 3x - 9
or x = 6

Reena age = 2x = 2*6 = 12 year.

4. I have a few sweets to be distributed. If I keep 2, 3 or 4 in a pack, I am left with one sweet. If I keep 5 in a pack, I am left with none. What is the minimum number of sweets I have to pack and distribute ?

Answer: Option A

Explanation:

The required number will be such that it leaves a reminder of 1 when divided by 2, 3 or 4 and no reminder when divided by 5. Such a number is 25 among options

5. A student got twice as many sums wrong as he got right. If he attempted 48 sums in all, how many did he solve correctly ?

Answer: Option B

Explanation:

Suppose boy got x sums right and 2x sums wrong,
then,
x+2x = 48
=> 3x = 48
=> x = 16