Subtract 70/21 from 20/80
1st number: 20/80, 2nd number: 3 7/21
20/80 - 70/21 is -37/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 80 × 21 = 1680,
20/80 = 20 × 21/80 × 21 = 420/1680 - Likewise, for the 2nd fraction, since 21 × 80 = 1680,
70/21 = 70 × 80/21 × 80 = 5600/1680 - Subtract the two like fractions:
420/1680 - 5600/1680 = 420 - 5600/1680 = -5180/1680 - After reducing the fraction, the answer is -37/12
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