9514 1404 393
Answer:
B. 4 mi (the correct answer is marked)
Step-by-step explanation:
Corresponding sides are proportional:
AC/EC = AB/ED
AC = EC×AB/ED = (12 ft)×(7 mi)/(21 ft) = (84/21) mi
AC = 4 mi
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There is no need to convert from miles to feet, or vice versa, in this problem. The units of ft/ft cancel, so the resulting units associated with the numerical value are miles. (If the unwanted units don't cancel the proportion is written incorrectly.)
