Subtract 72/40 from 20/18
1st number: 1 2/18, 2nd number: 1 32/40
20/18 - 72/40 is -31/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 18 × 20 = 360,
20/18 = 20 × 20/18 × 20 = 400/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
72/40 = 72 × 9/40 × 9 = 648/360 - Subtract the two like fractions:
400/360 - 648/360 = 400 - 648/360 = -248/360 - After reducing the fraction, the answer is -31/45
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