Subtract 21/30 from 15/8
1st number: 1 7/8, 2nd number: 21/30
15/8 - 21/30 is 47/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 30 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 8 × 15 = 120,
15/8 = 15 × 15/8 × 15 = 225/120 - Likewise, for the 2nd fraction, since 30 × 4 = 120,
21/30 = 21 × 4/30 × 4 = 84/120 - Subtract the two like fractions:
225/120 - 84/120 = 225 - 84/120 = 141/120 - After reducing the fraction, the answer is 47/40
- In mixed form: 17/40
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