Subtract 72/15 from 30/40
1st number: 30/40, 2nd number: 4 12/15
30/40 - 72/15 is -81/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 15 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 40 × 3 = 120,
30/40 = 30 × 3/40 × 3 = 90/120 - Likewise, for the 2nd fraction, since 15 × 8 = 120,
72/15 = 72 × 8/15 × 8 = 576/120 - Subtract the two like fractions:
90/120 - 576/120 = 90 - 576/120 = -486/120 - After reducing the fraction, the answer is -81/20
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