Subtract 21/15 from 42/8
1st number: 5 2/8, 2nd number: 1 6/15
42/8 - 21/15 is 77/20.
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,
42/8 = 42 × 15/8 × 15 = 630/120 - Likewise, for the 2nd fraction, since 15 × 8 = 120,
21/15 = 21 × 8/15 × 8 = 168/120 - Subtract the two like fractions:
630/120 - 168/120 = 630 - 168/120 = 462/120 - After reducing the fraction, the answer is 77/20
- In mixed form: 317/20
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