7. which is the best buy? 6 shirts for $25.50 4 shirts for $18.00 5 shirts for $21

5 shirts for $21

the 6 deal would be $4.25 for each shirt

4 deal would be $4.50 for each shirt

and the 5 deal is the cheapest because its $4.20 for each shirt

8 2/3 is the answer

step-by-step explanation: just use a calculator

option a is correct.

step-by-step explanation:

scale factor: it is used to find proportional measurements.

proportions means having the same ratio.

scale factor is the ratio of the model measurement to the actual measurement in a simplest form.

or we can say that the ratio of any two corresponding lengths in two similar geometric figures

if the scale factor is more than 1, then it is an enlargement,

if the scale factor less than 1, then it is a reduction.

given the two geometric figure:

by definition of proportions, we have