Subtract 81/49 from 80/21
1st number: 3 17/21, 2nd number: 1 32/49
80/21 - 81/49 is 317/147.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 49 is 147
Next, find the equivalent fraction of both fractional numbers with denominator 147 - For the 1st fraction, since 21 × 7 = 147,
80/21 = 80 × 7/21 × 7 = 560/147 - Likewise, for the 2nd fraction, since 49 × 3 = 147,
81/49 = 81 × 3/49 × 3 = 243/147 - Subtract the two like fractions:
560/147 - 243/147 = 560 - 243/147 = 317/147 - In mixed form: 223/147
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