Subtract 72/40 from 18/30
1st number: 18/30, 2nd number: 1 32/40
18/30 - 72/40 is -6/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 30 × 4 = 120,
18/30 = 18 × 4/30 × 4 = 72/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
72/40 = 72 × 3/40 × 3 = 216/120 - Subtract the two like fractions:
72/120 - 216/120 = 72 - 216/120 = -144/120 - After reducing the fraction, the answer is -6/5
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