Subtract 42/9 from 90/7
1st number: 12 6/7, 2nd number: 4 6/9
90/7 - 42/9 is 172/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 7 × 9 = 63,
90/7 = 90 × 9/7 × 9 = 810/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
42/9 = 42 × 7/9 × 7 = 294/63 - Subtract the two like fractions:
810/63 - 294/63 = 810 - 294/63 = 516/63 - After reducing the fraction, the answer is 172/21
- In mixed form: 84/21
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