Frank has devised a formula for his catering business that calculates the number of meatballs he needs to prepare. the formula is , where c = number of children; m = number of meatballs; a = number of adults. how many meatballs are required for a party of 25 adults and 5 children?

Just plug in the numbers into the equation.

m = 4a + 2c

a = adults
c = children
m = meatballs

The information given says there are 25 adults and 5 children. So now:

a = 25
and
c = 5
in the equation m = 4a + 2c

Now plug in the values. 
m = 4(25) + 2(5)
m = 100 + 10
m = 110

This means that 110 meatballs are required for 25 adults and 5 children.