Subtract 5/21 from 42/9
1st number: 4 6/9, 2nd number: 5/21
42/9 - 5/21 is 31/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 9 × 7 = 63,
42/9 = 42 × 7/9 × 7 = 294/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
5/21 = 5 × 3/21 × 3 = 15/63 - Subtract the two like fractions:
294/63 - 15/63 = 294 - 15/63 = 279/63 - After reducing the fraction, the answer is 31/7
- In mixed form: 43/7
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