Posted by Saraphina on .
In a pet store there are 4 more cats than dogs and the ratio of cats to dogs is 12 to 9.What is the total number of cats and dogs in the pet store?

Algebra 
Reiny,
let the number of cats be 12x
let the number of dogs be 9x
12x  9x = 4
3x=4
x = 4/3
number of cats = 12x = 12(4/3) = 16
number of dogs = 9(4/3) = 12
for a total of 28 cats and dogs.
check:
16:12 = 4:3 or the given 12:9
cats  dogs = 1612 = 4 , thus 4 more cats than dogs