Subtract 20/72 from 21/18
1st number: 1 3/18, 2nd number: 20/72
21/18 - 20/72 is 8/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 18 × 4 = 72,
21/18 = 21 × 4/18 × 4 = 84/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
20/72 = 20 × 1/72 × 1 = 20/72 - Subtract the two like fractions:
84/72 - 20/72 = 84 - 20/72 = 64/72 - After reducing the fraction, the answer is 8/9
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