Answer:
$42.12
Step-by-step explanation:
Calculation for How much will Gretta pay in total for this transaction
First step is to calculate the new price
New price=$65- ($65*40%)
New price=$65-26
New price=$39
Second step is to calculate the sales tax amount
Sales tax=8%*39
Sales tax=$3.12
Last step is to calculate How much will Gretta pay in total for this transaction using this formula
Total Amount to be paid=New price+Sales tax
Let plug in the formula
Total Amount to be paid=$39+$3.12
Total Amount to be paid=$42.12
Therefore the amount that Gretta will pay in total for this transaction will be $42.12
I got that x equals -3.809523 (repeating)
10.…….……......................

Actually Welcome to the concept of calculations of bills.
The bill calculation goes as equation,
y = $250 + n*($10)
here, n = number of lines,
1.) For n = 2 , Y = cost = 250 + 20 = $270
2.) for n = 4 , Y = $290
3.) for n = 6 , Y = $310
4.) for n = x, Y = $250 + x*($10)
for lastly 12 members we get as,
Y = 250 + (12)*(10) = 250+120 = $370
Divide $55.65 by 7 to get the cost of 1 key chain ($7.95). Then multiply the cost of 1 by 12 and get $95.40