Answer:
$111.59
Step-by-step explanation:
The total amount of the purchase was the cost of the computer plus the sales tax:
$1,257*1,06= $1,332.42
Now, to determine the interest that they will have to pay, you have to consider that the interest rate is 16,75% APR that is the annual percentage rate but as only 6 month have passed, the interest rate at this point that they have to pay is 8.375%:
$1,332.42*8.375%= $111.59
The interest that they will be charged is $111.59
Let L be the low copper alloy and H be the high copper alloy.
We need 0.15L + 0.60H = 0.42 and L + H = 100
L=100 - H
Substituting this into the second equation for L, we get:
0.15(100-H) + 0.60H = 0.42(H+L)
15 - 0.15H + 0.60H = 0.42(H+100-H)
15 + 0.45H = 0.42(100)
0.45H = 42 - 15 = 27
H = 27/.45 = 60 lbs
Back substitution, L = 40 lbs.
The angle that you need to choose is 2 I think