Subtract 21/80 from 28/21
1st number: 1 7/21, 2nd number: 21/80
28/21 - 21/80 is 257/240.
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,
28/21 = 28 × 80/21 × 80 = 2240/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
21/80 = 21 × 21/80 × 21 = 441/1680 - Subtract the two like fractions:
2240/1680 - 441/1680 = 2240 - 441/1680 = 1799/1680 - After reducing the fraction, the answer is 257/240
- In mixed form: 117/240
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