Subtract 5/21 from 42/8
1st number: 5 2/8, 2nd number: 5/21
42/8 - 5/21 is 421/84.
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,
42/8 = 42 × 21/8 × 21 = 882/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
5/21 = 5 × 8/21 × 8 = 40/168 - Subtract the two like fractions:
882/168 - 40/168 = 882 - 40/168 = 842/168 - After reducing the fraction, the answer is 421/84
- In mixed form: 51/84
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