Subtract 21/30 from 30/72
30/72 - 21/30 is -17/60.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 30 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
30/72 = 30 × 5/72 × 5 = 150/360 - Likewise, for the 2nd fraction, since 30 × 12 = 360,
21/30 = 21 × 12/30 × 12 = 252/360 - Subtract the two like fractions:
150/360 - 252/360 = 150 - 252/360 = -102/360 - After reducing the fraction, the answer is -17/60
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