Subtract 18/40 from 81/15
1st number: 5 6/15, 2nd number: 18/40
81/15 - 18/40 is 99/20.
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,
81/15 = 81 × 8/15 × 8 = 648/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
18/40 = 18 × 3/40 × 3 = 54/120 - Subtract the two like fractions:
648/120 - 54/120 = 648 - 54/120 = 594/120 - After reducing the fraction, the answer is 99/20
- In mixed form: 419/20
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