Subtract 90/70 from 1/21
1st number: 1/21, 2nd number: 1 20/70
1/21 - 90/70 is -26/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
1/21 = 1 × 10/21 × 10 = 10/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
90/70 = 90 × 3/70 × 3 = 270/210 - Subtract the two like fractions:
10/210 - 270/210 = 10 - 270/210 = -260/210 - After reducing the fraction, the answer is -26/21
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