Subtract 21/9 from 18/72
1st number: 18/72, 2nd number: 2 3/9
18/72 - 21/9 is -25/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 9 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 72 × 1 = 72,
18/72 = 18 × 1/72 × 1 = 18/72 - Likewise, for the 2nd fraction, since 9 × 8 = 72,
21/9 = 21 × 8/9 × 8 = 168/72 - Subtract the two like fractions:
18/72 - 168/72 = 18 - 168/72 = -150/72 - After reducing the fraction, the answer is -25/12
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