$6.63
Set up a proportion for the situation and solve for the unknown quantity. Round to the hundredths place because we are dealing with money.
See details:
Answer:
A
Step-by-step explanation:
[] The fractions are

[] I see that 21 is a multiple of 7, so this one will be simple to solve.
-> 21 / 7 = 3, so we can do the following:

[] Now they have a common denominator of <u>21</u>
Have a nice day!
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- Heather