Kevin is 39 years old and daniel is 3 years old. how many years will it take until kevin is only 4 times as old as daniel?

K=39 and d=3

(k+y)/(d+y)=4  using k and d given...

(39+y)/(3+y)=4  multiplying both sides by (3+y)

39+y=12+4y  subtracting 4y from both sides

39-3y=12  subtracting 39 from both sides

-3y=-27  dividing both sides by -3

y=9

So in nine years Kevin will be four times as old as Daniel.

check...

(39+9)/(3+9)=4

48/12=4

4=4

These are the multiples of 15 but what you are probably asking or what are the factors of 15