Subtract 72/20 from 45/30
1st number: 1 15/30, 2nd number: 3 12/20
45/30 - 72/20 is -21/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 20 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 30 × 2 = 60,
45/30 = 45 × 2/30 × 2 = 90/60 - Likewise, for the 2nd fraction, since 20 × 3 = 60,
72/20 = 72 × 3/20 × 3 = 216/60 - Subtract the two like fractions:
90/60 - 216/60 = 90 - 216/60 = -126/60 - After reducing the fraction, the answer is -21/10
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