Subtract 20/70 from 90/45
1st number: 2 0/45, 2nd number: 20/70
90/45 - 20/70 is 12/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 45 × 14 = 630,
90/45 = 90 × 14/45 × 14 = 1260/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
20/70 = 20 × 9/70 × 9 = 180/630 - Subtract the two like fractions:
1260/630 - 180/630 = 1260 - 180/630 = 1080/630 - After reducing the fraction, the answer is 12/7
- In mixed form: 15/7
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