Subtract 9/15 from 21/8
1st number: 2 5/8, 2nd number: 9/15
21/8 - 9/15 is 81/40.
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,
9/15 = 9 × 8/15 × 8 = 72/120 - Subtract the two like fractions:
315/120 - 72/120 = 315 - 72/120 = 243/120 - After reducing the fraction, the answer is 81/40
- In mixed form: 21/40
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