Subtract 90/70 from 12/21
1st number: 12/21, 2nd number: 1 20/70
12/21 - 90/70 is -5/7.
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,
12/21 = 12 × 10/21 × 10 = 120/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
90/70 = 90 × 3/70 × 3 = 270/210 - Subtract the two like fractions:
120/210 - 270/210 = 120 - 270/210 = -150/210 - After reducing the fraction, the answer is -5/7
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