Subtract 18/21 from 42/15
1st number: 2 12/15, 2nd number: 18/21
42/15 - 18/21 is 68/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
42/15 = 42 × 7/15 × 7 = 294/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
18/21 = 18 × 5/21 × 5 = 90/105 - Subtract the two like fractions:
294/105 - 90/105 = 294 - 90/105 = 204/105 - After reducing the fraction, the answer is 68/35
- In mixed form: 133/35
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