6 / 88 = 21/x
cross multiply
(6)(x) = (21)(88)
6x = 1848
x = 1848/6
x = 308 <==
12.65+21.55=34.20
34.20*.15=5.13
.15 is the percentage of the tip they pay in decimal form in order to multiply it on a calculator.
Answer is $5.13
Answer:
1.33
Step-by-step explanation:
I suppose you mean

Differentiate one term at a time.
Rewrite the first term as

Then the product rule says

Then with the power and chain rules,

Simplify this a bit by factoring out
:

For the second term, recall that

Then by the chain rule,

So we have

and we can simplify this by factoring out
to end up with

50 is 46.82 rounded to the nearest ten