Subtract 90/72 from 21/30
1st number: 21/30, 2nd number: 1 18/72
21/30 - 90/72 is -11/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 30 × 12 = 360,
21/30 = 21 × 12/30 × 12 = 252/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
90/72 = 90 × 5/72 × 5 = 450/360 - Subtract the two like fractions:
252/360 - 450/360 = 252 - 450/360 = -198/360 - After reducing the fraction, the answer is -11/20
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