Question 729228
Let qty of fudge be x pounds & qty of toffee be y pounds per month	
	
They make an average of 154 pounds of fudge and toffee combined each month	
	
x+y=154	(1)
	
They sell a pound of fudge for $9.64 and a pound of toffee for $6.44. Mandy's averages $1,231.76 each month in fudge and toffee sales. On average,	
	
So  cost of monthly fudge&toffee is  9.64*x+6.44*y=1231.76 	
	
9.64x+6.44y=1231.76	;(2)
	
multiply eq (1) by 9.64 & then subtract 2 from 1	
	
9.64x+9.64y=154*9.64	
9.64x+9.64y=1484.56   	(1')
9.64x+6.44y=1231.76	;(2)
-----------------------
(9.64-6.44)y=1484.64-1231.76	
	
3.2y=252.8	
	
y=252.8/3.2=79 pounda	
	
In order to solve for x, take the value for y and substitute it back into either one of the original equations.	
	
x+79=154	
	
x=154-79=75 pounds	So they make 75 pounds of fudge & 79 pounds of toffee per month
so monthly cost is	
9.64*75+6.44*79=1231.76