Subtract 21/70 from 18/9
1st number: 2 0/9, 2nd number: 21/70
18/9 - 21/70 is 17/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 9 × 70 = 630,
18/9 = 18 × 70/9 × 70 = 1260/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
21/70 = 21 × 9/70 × 9 = 189/630 - Subtract the two like fractions:
1260/630 - 189/630 = 1260 - 189/630 = 1071/630 - After reducing the fraction, the answer is 17/10
- In mixed form: 17/10
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