Subtract 72/20 from 12/8
1st number: 1 4/8, 2nd number: 3 12/20
12/8 - 72/20 is -21/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 20 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 8 × 5 = 40,
12/8 = 12 × 5/8 × 5 = 60/40 - Likewise, for the 2nd fraction, since 20 × 2 = 40,
72/20 = 72 × 2/20 × 2 = 144/40 - Subtract the two like fractions:
60/40 - 144/40 = 60 - 144/40 = -84/40 - After reducing the fraction, the answer is -21/10
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