Subtract 40/21 from 90/9
1st number: 10 0/9, 2nd number: 1 19/21
90/9 - 40/21 is 170/21.
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,
90/9 = 90 × 7/9 × 7 = 630/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
40/21 = 40 × 3/21 × 3 = 120/63 - Subtract the two like fractions:
630/63 - 120/63 = 630 - 120/63 = 510/63 - After reducing the fraction, the answer is 170/21
- In mixed form: 82/21
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