Subtract 20/40 from 80/21
1st number: 3 17/21, 2nd number: 20/40
80/21 - 20/40 is 139/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
80/21 = 80 × 40/21 × 40 = 3200/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
20/40 = 20 × 21/40 × 21 = 420/840 - Subtract the two like fractions:
3200/840 - 420/840 = 3200 - 420/840 = 2780/840 - After reducing the fraction, the answer is 139/42
- In mixed form: 313/42
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