Subtract 20/45 from 21/28
21/28 - 20/45 is 11/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 45 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 28 × 45 = 1260,
21/28 = 21 × 45/28 × 45 = 945/1260 - Likewise, for the 2nd fraction, since 45 × 28 = 1260,
20/45 = 20 × 28/45 × 28 = 560/1260 - Subtract the two like fractions:
945/1260 - 560/1260 = 945 - 560/1260 = 385/1260 - After reducing the fraction, the answer is 11/36
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