Subtract 98/20 from 90/21
1st number: 4 6/21, 2nd number: 4 18/20
90/21 - 98/20 is -43/70.
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,
90/21 = 90 × 20/21 × 20 = 1800/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
98/20 = 98 × 21/20 × 21 = 2058/420 - Subtract the two like fractions:
1800/420 - 2058/420 = 1800 - 2058/420 = -258/420 - After reducing the fraction, the answer is -43/70
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