Subtract 28/21 from 20/8
1st number: 2 4/8, 2nd number: 1 7/21
20/8 - 28/21 is 7/6.
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,
28/21 = 28 × 8/21 × 8 = 224/168 - Subtract the two like fractions:
420/168 - 224/168 = 420 - 224/168 = 196/168 - After reducing the fraction, the answer is 7/6
- In mixed form: 11/6
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