Subtract 21/80 from 15/8
1st number: 1 7/8, 2nd number: 21/80
15/8 - 21/80 is 129/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 80 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 8 × 10 = 80,
15/8 = 15 × 10/8 × 10 = 150/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
21/80 = 21 × 1/80 × 1 = 21/80 - Subtract the two like fractions:
150/80 - 21/80 = 150 - 21/80 = 129/80 - In mixed form: 149/80
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