Answer: 3.387 miles (approximate)
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Work Shown:
Method 1
(3 miles)/(62 min) = (x miles)/(70 min)
3/62 = x/70
3*70 = 62x
210 = 62x
x = 210/62
x = 3.38709677 approximately
She walks about 3.387 miles in 70 minutes.
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Method 2
She walks 3 miles in 62 minutes. Her unit rate is 3/62 of a mile per minute.
distance = rate*time
d = r*t
d = (3/62 mi per min)*(70 min)
d = (3/62)*(70)
d = 3.38709677 approximately