Question

You want a snack. One cookie has 130 calories. An orange has 35 calories. What is the ratio of the calories in an orange to the calories in the cookie?

Answer 1

We want the ratio of calories of an orange to a cookie and are told that an orange has 35 calories and a cookie has 130 so:

O:C=35:130

The greatest common factor of 35 and 130 is the product of the shared primes of the numbers prime factorization.

35=5*7 and 130=2*5*13, so the GCF is just 5, so divide each term by 5

O:C=7:26