Subtract 28/21 from 42/5
1st number: 8 2/5, 2nd number: 1 7/21
42/5 - 28/21 is 106/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
42/5 = 42 × 21/5 × 21 = 882/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
28/21 = 28 × 5/21 × 5 = 140/105 - Subtract the two like fractions:
882/105 - 140/105 = 882 - 140/105 = 742/105 - After reducing the fraction, the answer is 106/15
- In mixed form: 71/15
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