13/8
alternative forms:
1 5/8, 1.625
2 1/8-1/2
multiply 2 and 8
16+1/8-1/2
add 16 to 1
17/8-1/2
least common multiple of 8 and 2 is 8. Convert 17/8=2.125 and 1/2=0.5 to fractions with denominator 8.
17/8-4/8
subtract numerators and put denominators as only one 8.
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13/8
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