Answer :
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~
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~
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
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