Answer :V=πr2h=π·72·11≈1693.31844
Step-by-step explanation:
First off, let's convert the percentages to decimal format, so our 77% turns to 77/100 or 0.77, and our 55% turns to 55/100 or 0.55 and so on
now, the sum of both salines, must add up to the 77% mixture, let's say is "y"
so, 11 + 4 = y, and whatever the concentration level is, must also sum up to the mixture's concentration of 77%
anyway thus

solve for "x"
She gets $2.75 back if that’s what you’re asking.
The general formula for geometric series is tn = a×rⁿ⁻¹. In this question, a (or a1) is 3, and r is 1.1, therefore the first ten terms would be 3×1.1⁰ (3) , 3×1.1¹ (3.3), 3×1.1² (3.63) and so on up until you get to 3×1.1⁹ or 7.07.