Subtract 21/18 from 28/20
1st number: 1 8/20, 2nd number: 1 3/18
28/20 - 21/18 is 7/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 18 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
28/20 = 28 × 9/20 × 9 = 252/180 - Likewise, for the 2nd fraction, since 18 × 10 = 180,
21/18 = 21 × 10/18 × 10 = 210/180 - Subtract the two like fractions:
252/180 - 210/180 = 252 - 210/180 = 42/180 - After reducing the fraction, the answer is 7/30
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