Subtract 21/7 from 21/80
1st number: 21/80, 2nd number: 3 0/7
21/80 - 21/7 is -219/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 7 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 80 × 7 = 560,
21/80 = 21 × 7/80 × 7 = 147/560 - Likewise, for the 2nd fraction, since 7 × 80 = 560,
21/7 = 21 × 80/7 × 80 = 1680/560 - Subtract the two like fractions:
147/560 - 1680/560 = 147 - 1680/560 = -1533/560 - After reducing the fraction, the answer is -219/80
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