Subtract 7/21 from 42/24
1st number: 1 18/24, 2nd number: 7/21
42/24 - 7/21 is 17/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 24 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 24 × 7 = 168,
42/24 = 42 × 7/24 × 7 = 294/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
7/21 = 7 × 8/21 × 8 = 56/168 - Subtract the two like fractions:
294/168 - 56/168 = 294 - 56/168 = 238/168 - After reducing the fraction, the answer is 17/12
- In mixed form: 15/12
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