Subtract 20/70 from 72/21
1st number: 3 9/21, 2nd number: 20/70
72/21 - 20/70 is 22/7.
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,
72/21 = 72 × 10/21 × 10 = 720/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
20/70 = 20 × 3/70 × 3 = 60/210 - Subtract the two like fractions:
720/210 - 60/210 = 720 - 60/210 = 660/210 - After reducing the fraction, the answer is 22/7
- In mixed form: 31/7
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