Subtract 80/21 from 30/40
1st number: 30/40, 2nd number: 3 17/21
30/40 - 80/21 is -257/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
30/40 = 30 × 21/40 × 21 = 630/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
80/21 = 80 × 40/21 × 40 = 3200/840 - Subtract the two like fractions:
630/840 - 3200/840 = 630 - 3200/840 = -2570/840 - After reducing the fraction, the answer is -257/84
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