Keisha spent all day baking pies and cookie cakes for Party. Each pie had to bake for 48 minutes, and each cookie cake had to bake for 18 minutes. All together , keisha baked 9 desserts one at a time for a total of 4 hours and 12 minutes. How many cookie cakes did keisha bake?

Answer 1

Let x = number of baked pies
Let y= number of baked cookie cakes

Equations:
48x + 18y= 252 (1)
(Note: 4 hours and 12 minutes is equivalent to 252 minutes)

x + y = 9 (2) y=9-x

To find x;
Through substitution method
48x + 18y= 252
48x + 18(9-x)= 252
48x + 162-18x =252
162 + 30x = 252
30x = 252 - 162
x = 90/ 30
x = 3

So since x = 3;
x + y = 9
3 + y = 9
y = 9 - 3
y = 6

Therefore, there are a total of 6 baked cookie cakes in all. :)