Subtract 8/21 from 81/70
1st number: 1 11/70, 2nd number: 8/21
81/70 - 8/21 is 163/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
81/70 = 81 × 3/70 × 3 = 243/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
8/21 = 8 × 10/21 × 10 = 80/210 - Subtract the two like fractions:
243/210 - 80/210 = 243 - 80/210 = 163/210
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