On thanksgiving your grandmother and mother came to the agreement that grandma would make 7 rolls for every 4 pies that you all made .
If grandma made
91 rolls how many pies does your mom need?

52

Explanation:

Divide 91 by 7. This will be 13. (That is how many times your grandma made & rolls.) Now multiply 13 by 4 because you will have to make 4 pies 13 times in order to have the right amount. This will be 52. To check your work, 7 divided by 4 equals 1.75. If 52 is the right answer 91 divided by 52 should equal 1.75 as well. (which it does)

the thirteen colonies are:

connecticut, delaware, georgia, maryland, massachusetts, new jersey, new york, new hampshire, north carolina, pennsylvania, rhode island, south carolina, virginia