Subtract 15/35 from 42/21
1st number: 2 0/21, 2nd number: 15/35
42/21 - 15/35 is 11/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 35 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
42/21 = 42 × 5/21 × 5 = 210/105 - Likewise, for the 2nd fraction, since 35 × 3 = 105,
15/35 = 15 × 3/35 × 3 = 45/105 - Subtract the two like fractions:
210/105 - 45/105 = 210 - 45/105 = 165/105 - After reducing the fraction, the answer is 11/7
- In mixed form: 14/7
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