Subtract 1/8 from 42/21
1st number: 2 0/21, 2nd number: 1/8
42/21 - 1/8 is 15/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
42/21 = 42 × 8/21 × 8 = 336/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
1/8 = 1 × 21/8 × 21 = 21/168 - Subtract the two like fractions:
336/168 - 21/168 = 336 - 21/168 = 315/168 - After reducing the fraction, the answer is 15/8
- In mixed form: 17/8
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