Subtract 20/70 from 72/42
1st number: 1 30/42, 2nd number: 20/70
72/42 - 20/70 is 10/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
72/42 = 72 × 5/42 × 5 = 360/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
20/70 = 20 × 3/70 × 3 = 60/210 - Subtract the two like fractions:
360/210 - 60/210 = 360 - 60/210 = 300/210 - After reducing the fraction, the answer is 10/7
- In mixed form: 13/7
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