1 yard is 3 ft, so 70 yards is (70 yd)×(3 ft/yd) = 210 feet.
The area of the pavement is the product of its length and width:
area = (210 ft)(10 ft) = 2100 ft²
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If you keep the units with the numbers as I have done here, you find that the product of (10 ft) and (70 yd) does not have the units of ft². Rather, the units are ft·yd, which is <em>not what the problem is asking for</em>.
