Question

A restaurant sells only two desserts,pie and cake.A piece of pie cost $4.A piece of cake cost $5.The restaurant sells 100 desserts,which cost a total of $473.How many pieces of pie did they sell (HELP NEEDED FAST)

Answer 1

Pie = x
cake = y

x + y = 100
4x + 5y = 473
4x + 4y = 400
substract it
y = 73

x + y = 100
x + 73 = 100
x = 100 - 73 = 27

Answer 2

Let p and c be the pieces of pie and cake respectively.

We have p+ c= 100 (because the total number of pieces of pie and cake is 100).

On the other hand, we have $4p+ $5c= $473
or 4p+ 5c= 473

p+c=100
4p+5c=473

Solving the set of equations above, we have: p= 27, c=73.

They sold 27 pieces of pie~