Question 678892
40% = 40/100 = .4
.4(50) = 20 miles the  first day
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50 - 20 = 30 miles remaining
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.5(30) = 15 miles the second day
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{{{highlight_green(15)}}} miles remaining
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Alternatively,
If 40% walked in the first day, then 60% remaining (100-40=60)
.60(50) = 30 left
.50(30) = 15 walked
30-15 = 15 remaining
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