Subtract 90/20 from 40/21
1st number: 1 19/21, 2nd number: 4 10/20
40/21 - 90/20 is -109/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
40/21 = 40 × 20/21 × 20 = 800/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
90/20 = 90 × 21/20 × 21 = 1890/420 - Subtract the two like fractions:
800/420 - 1890/420 = 800 - 1890/420 = -1090/420 - After reducing the fraction, the answer is -109/42
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