Subtract 1/21 from 28/8
1st number: 3 4/8, 2nd number: 1/21
28/8 - 1/21 is 145/42.
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,
28/8 = 28 × 21/8 × 21 = 588/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
1/21 = 1 × 8/21 × 8 = 8/168 - Subtract the two like fractions:
588/168 - 8/168 = 588 - 8/168 = 580/168 - After reducing the fraction, the answer is 145/42
- In mixed form: 319/42
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