Subtract 3/80 from 81/21
1st number: 3 18/21, 2nd number: 3/80
81/21 - 3/80 is 2139/560.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 21 × 80 = 1680,
81/21 = 81 × 80/21 × 80 = 6480/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
3/80 = 3 × 21/80 × 21 = 63/1680 - Subtract the two like fractions:
6480/1680 - 63/1680 = 6480 - 63/1680 = 6417/1680 - After reducing the fraction, the answer is 2139/560
- In mixed form: 3459/560
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