Question

Tonya is twice Kevin's age.
In 3 years, Tonya will be 17.
How old is Kevin?
A.
6
B.
20
C.
7
D.
8

Answer 1

Hi there, Kevin's age would be C. 7. This is because Tonya right now is 14. 7 is half of 14.

Answer 2

For this case we have the following variables:

T: Tonya's age

K: Kevin's age

If Tonya is twice Kevin's age we have:

$T = 2K$

In three years Tonya will have 17, it means:

$T +3=17$

We have a system of two equations with two unknowns:

$T=2K$

$T+3=17$

From the second equation we have:$T = 17-3 = 14$

Substituting T = 14 in the first equation we have:

$14 = 2K$

Clearing K:

$\frac{14}{2}=K$

So, Kevin is 7 years old

Answer:

7 years

Option C