Subtract 72/20 from 18/10
1st number: 1 8/10, 2nd number: 3 12/20
18/10 - 72/20 is -9/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 20 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 10 × 2 = 20,
18/10 = 18 × 2/10 × 2 = 36/20 - Likewise, for the 2nd fraction, since 20 × 1 = 20,
72/20 = 72 × 1/20 × 1 = 72/20 - Subtract the two like fractions:
36/20 - 72/20 = 36 - 72/20 = -36/20 - After reducing the fraction, the answer is -9/5
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