Subtract 9/42 from 21/15
1st number: 1 6/15, 2nd number: 9/42
21/15 - 9/42 is 83/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 15 × 14 = 210,
21/15 = 21 × 14/15 × 14 = 294/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
9/42 = 9 × 5/42 × 5 = 45/210 - Subtract the two like fractions:
294/210 - 45/210 = 294 - 45/210 = 249/210 - After reducing the fraction, the answer is 83/70
- In mixed form: 113/70
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