Answer:
Erin ran 12.5 miles
Luis ran 7.5
In all they ran 20 miles.
Explanation:
Erin: 5 x 3.5 = ?
Luis: 3 x 2.5 = ?
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5 x 2.5 = 12.5 . Erin ran 12.5 miles
3 x 2.5 = 7.5 . Luis ran 7.5 miles
7.5 + 12.5 = 20 miles
They ran 20 miles all together.
Hope this helps!