He did not walk 1/2 a mile. Because it's a round-trip, it's technically 2 miles long. so, in the end, he did not walk 1/4 of the trip. Hope this helps :)
The quotient may be greater than or less than the dividend or divisor. When the dividend is less than the divisor, the quotient will be less than one. When the dividend is greater than the divisor, the quotient will be greater than one.
