Subtract 20/9 from 90/7
1st number: 12 6/7, 2nd number: 2 2/9
90/7 - 20/9 is 670/63.
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,
20/9 = 20 × 7/9 × 7 = 140/63 - Subtract the two like fractions:
810/63 - 140/63 = 810 - 140/63 = 670/63 - In mixed form: 1040/63
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