Subtract 21/45 from 20/49
20/49 - 21/45 is -43/735.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 45 is 2205
Next, find the equivalent fraction of both fractional numbers with denominator 2205 - For the 1st fraction, since 49 × 45 = 2205,
20/49 = 20 × 45/49 × 45 = 900/2205 - Likewise, for the 2nd fraction, since 45 × 49 = 2205,
21/45 = 21 × 49/45 × 49 = 1029/2205 - Subtract the two like fractions:
900/2205 - 1029/2205 = 900 - 1029/2205 = -129/2205 - After reducing the fraction, the answer is -43/735
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