Subtract 80/28 from 20/21
1st number: 20/21, 2nd number: 2 24/28
20/21 - 80/28 is -40/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
20/21 = 20 × 4/21 × 4 = 80/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
80/28 = 80 × 3/28 × 3 = 240/84 - Subtract the two like fractions:
80/84 - 240/84 = 80 - 240/84 = -160/84 - After reducing the fraction, the answer is -40/21
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