Subtract 21/40 from 28/15
1st number: 1 13/15, 2nd number: 21/40
28/15 - 21/40 is 161/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 15 × 8 = 120,
28/15 = 28 × 8/15 × 8 = 224/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120 - Subtract the two like fractions:
224/120 - 63/120 = 224 - 63/120 = 161/120 - In mixed form: 141/120
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