Subtract 10/21 from 20/8
1st number: 2 4/8, 2nd number: 10/21
20/8 - 10/21 is 85/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
20/8 = 20 × 21/8 × 21 = 420/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
10/21 = 10 × 8/21 × 8 = 80/168 - Subtract the two like fractions:
420/168 - 80/168 = 420 - 80/168 = 340/168 - After reducing the fraction, the answer is 85/42
- In mixed form: 21/42
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