If 15 pies will serve 120 people how many pies will serve 152

To solve this problem, we should make a proportion.

15              x
         = 
120         152

(x is representing the unknown number of pies needed)

To solve equal proportions, you can use cross products.  This means multiplying the numerator of one fraction by the denominator of the other.

If done correctly, it should result in the equation 15 * 152 = 120x

Next, we simplify         2280=120x

And divide by 120         x= 19

19 pies will serve 152 people.