Subtract 72/20 from 42/80
1st number: 42/80, 2nd number: 3 12/20
42/80 - 72/20 is -123/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 20 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 80 × 1 = 80,
42/80 = 42 × 1/80 × 1 = 42/80 - Likewise, for the 2nd fraction, since 20 × 4 = 80,
72/20 = 72 × 4/20 × 4 = 288/80 - Subtract the two like fractions:
42/80 - 288/80 = 42 - 288/80 = -246/80 - After reducing the fraction, the answer is -123/40
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