Subtract 20/90 from 42/21
1st number: 2 0/21, 2nd number: 20/90
42/21 - 20/90 is 16/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
42/21 = 42 × 30/21 × 30 = 1260/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
20/90 = 20 × 7/90 × 7 = 140/630 - Subtract the two like fractions:
1260/630 - 140/630 = 1260 - 140/630 = 1120/630 - After reducing the fraction, the answer is 16/9
- In mixed form: 17/9
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