The present age of a father is 3 years more than three times the age

Question

Q. The present age of a father is 3 years more than three times the age of his son. Three years hence , father's age will be 10 years more than twice the age of the son. Present age of the father is..

A. 9

B. 10

C. 30

D. 33

E. 35

WiziusCareers1 · Answer

We get two equations
F = 3S + 3
and
F + 3 = 2(S + 3) + 10

Solving the two equations, we get
S = 10 and F = 33
Hence, the answer is (D).

BrentGMATPrepNow · Answer

We can also solve this question using  one variable

The present age of a father is 3 years more than three times the age of his son  
Let x = the PRESENT age of the son
So, 3x + 3 = the PRESENT age of the father

So, x +  3  = the son's age IN THREE YEARS
And 3x + 3 +  3  = the father's age IN THREE YEARS

Three years hence  , father's age will be 10 years more than twice the age of the son  
In other words: (father's age in 3 years) = 2(son's age in 3 years) + 10
In other words: (3x + 3 +  3 ) = 2(x +  3 ) + 10
Simplify: 3x + 6 = 2x + 16
Subtract 2x from both sides: x + 6 = 16
Subtract 6 from both sides: x = 10

This means the son's PRESENT age is 10 years old
Since 3x + 3 = the PRESENT age of the father, the father's present age = 3(10) + 3 = 33

Answer: D

Cheers,
Brent

EgmatQuantExpert · Answer

Solution

Given  
In this question, we are given that
 • The present age of a father is 3 years more than three times the age of his son. 
• Three years hence, father's age will be 10 years more than twice the age of the son.

To find  
We need to determine
 • Present age of the father

Approach and Working out  
We can solve this using the options also.

Given that the present age of a father is 3 years more than three times the age of his son, implies father’s age is a multiple of 3
 • Hence, the answer can be either 9 or 30 or 33

Checking the three options individually, we get:
 • If father’s present age is 9 (which is logically improbable), then son’s present age is 2.
Three years hence, son will be 5 and father will be 12, and 5 x 2 + 10 is not 12

• If father’s present age is 30, then son’s present age is 9.
Three years hence, son will be 12 and father will be 33, and 12 x 2 + 10 is not 33

• If father’s present age is 33, then son’s present age is 10.
Three years hence, son will be 13 and father will be 36, and 13 x 2 + 10 is 36

Thus, option D is the correct answer.

Correct Answer: Option D

ScottTargetTestPrep · Answer

Solution:

We can let F = the present age of the father and S = the present age of the son and create the equations:

F = 3S + 3

and
 
F + 3 = 2(S + 3) + 10

Substituting 3S + 3 for F in the second equation, we have:

3S + 3 + 3 = 2(S + 3) + 10

3S + 6 = 2S + 6 + 10

S = 10

Therefore, the present age of the father is F = 3(10) + 3 = 33.

Answer: D

bumpbot · Answer

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The present age of a father is 3 years more than three times the age

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