Subtract 20/21 from 90/70
1st number: 1 20/70, 2nd number: 20/21
90/70 - 20/21 is 1/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
90/70 = 90 × 3/70 × 3 = 270/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
20/21 = 20 × 10/21 × 10 = 200/210 - Subtract the two like fractions:
270/210 - 200/210 = 270 - 200/210 = 70/210 - After reducing the fraction, the answer is 1/3
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