Answer:
Step-by-step explanation:
Remark
If you learn how to do this, a part of science called dimensional analysis will come more easily to you. It looks like this.
7 yds [3 ft/yd] [12 in / ft] = 252 inches.
Notice how it works. In the first set of brackets, the yards cancel. You have 21 feet. In the second set of brackets, the feet cancel, and you are left with inches.
Proportions
If this does not appeal to you, you can do it the standard way.
1 yard / 3 feet = 7 yards / x (feet) Cross Multiply
1 yard * x = 7 yards * 3 feet. Divide by yards
1 yard * x / yard = 7 yards * 3 feet/yds The yards cancel
x = 21 feet
1 foot / 12 inches = 21 feet / x Cross Multiply
1 foot * x = 12 inches * 21 feet Divide by ft
1 foot *x / foot = 12 inches *21 ft/ft
x = 252 inches
Answer
252 inches
