Subtract 15/8 from 21/80
1st number: 21/80, 2nd number: 1 7/8
21/80 - 15/8 is -129/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 8 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 80 × 1 = 80,
21/80 = 21 × 1/80 × 1 = 21/80 - Likewise, for the 2nd fraction, since 8 × 10 = 80,
15/8 = 15 × 10/8 × 10 = 150/80 - Subtract the two like fractions:
21/80 - 150/80 = 21 - 150/80 = -129/80
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