Subtract 21/20 from 45/49
1st number: 45/49, 2nd number: 1 1/20
45/49 - 21/20 is -129/980.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 20 is 980
Next, find the equivalent fraction of both fractional numbers with denominator 980 - For the 1st fraction, since 49 × 20 = 980,
45/49 = 45 × 20/49 × 20 = 900/980 - Likewise, for the 2nd fraction, since 20 × 49 = 980,
21/20 = 21 × 49/20 × 49 = 1029/980 - Subtract the two like fractions:
900/980 - 1029/980 = 900 - 1029/980 = -129/980
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