Answer:
11 quarters
Step-by-step explanation:
If Thomas ignores the extra 3 dimes, he can arrange his coins in groups of 3 dimes and 1 quarter, each group valued at 55¢. It takes
... 6.05/0.55 = 11
groups to bring the total value to the $6.05 remaining after ignoring the extra dimes.
Thomas has 11 quarters and 36 dimes.
It comes from integrating by parts twice. Let

Recall the IBP formula,

Let


Then

Apply IBP once more, with


Notice that the ∫ v du term contains the original integral, so that




$12.48/6= $2.08
$14.42/7= $2.06
$10.35/5= $2.07
So you are looking for the best deal.
The best deal would be:
B.) 7 bottles for $10.35
Hope that helps!!
Have a wonderful day!!