Answer:
Bill should use 4.5 pounds of the candy costing 45 cents and 2.5 pounds of the candy costing 65 cents.
Step-by-step explanation:
With the information provided, you can say that the sum of the pounds of each type of candy is equal to 7, which can be expressed as:
x+y=7
Also, the statement indicates the 7 pound box costs $3.65 and you can say that the sum of the results of multiplying the price of each candy for the number of pounds is equal to $3.65, which is:
0.45x+0.65y=3.65
You have the following equations:
x+y=7 (1)
0.45x+0.65y=3.65 (2)
Now, you have to solve for x in (1):
x=7-y (3)
Then, you have to replace (3) in (2):
0.45(7-y)+0.65y=3.65
3.15-0.45y+0.65y=3.65
0.20y=0.50
y=0.50/0.20
y=2.5
Finally, you can replace the value of y in (3) to find x:
x=7-y
x=7-2.5
x=4.5
According to this, the answer is that Bill should use 4.5 pounds of the candy costing 45 cents and 2.5 pounds of the candy costing 65 cents.
