Subtract 20/15 from 21/8
1st number: 2 5/8, 2nd number: 1 5/15
21/8 - 20/15 is 31/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 15 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 8 × 15 = 120,
21/8 = 21 × 15/8 × 15 = 315/120 - Likewise, for the 2nd fraction, since 15 × 8 = 120,
20/15 = 20 × 8/15 × 8 = 160/120 - Subtract the two like fractions:
315/120 - 160/120 = 315 - 160/120 = 155/120 - After reducing the fraction, the answer is 31/24
- In mixed form: 17/24
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