Subtract 5/70 from 20/42
20/42 - 5/70 is 17/42.
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,
20/42 = 20 × 5/42 × 5 = 100/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
5/70 = 5 × 3/70 × 3 = 15/210 - Subtract the two like fractions:
100/210 - 15/210 = 100 - 15/210 = 85/210 - After reducing the fraction, the answer is 17/42
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