Subtract 45/21 from 25/8, Solve 3 1/8

Subtract 45/21 from 25/8

1^st number: 3 1/8, 2^nd number: 2 3/21

25/8 - 45/21 is 55/56.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 8 × 21 = 168,
25/8 = 25 × 21/8 × 21 = 525/168
Likewise, for the 2nd fraction, since 21 × 8 = 168,
45/21 = 45 × 8/21 × 8 = 360/168
Subtract the two like fractions:
525/168 - 360/168 = 525 - 360/168 = 165/168
After reducing the fraction, the answer is 55/56

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