Problema Solution

Question 16

Mary is 3 times older than her brother Alex. After five years, she will be twice of his age. Find their present ages.

Answer

A) 4, 12

B) 5, 15

C) 3, 9

D) 6, 18

A) Approx 66138 lb

B) Approx 33069 lb

C) Approx 2578 lb

D) Approx 7128 lb

Answer provided by our tutors

Question 16

Mary is 3 times older than her brother Alex. After five years, she will be twice of his age. Find their present ages.

Answer

A) 4, 12

B) 5, 15

C) 3, 9

D) 6, 18

Solution:

Mary: 3x years old

Alex: x years old

The equation is

3x + 5 = 2(x+5)

x = 5

So their present age is 5,15

We choose (B)