Subtract 7/70 from 20/21
20/21 - 7/70 is 179/210.
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,
20/21 = 20 × 10/21 × 10 = 200/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
7/70 = 7 × 3/70 × 3 = 21/210 - Subtract the two like fractions:
200/210 - 21/210 = 200 - 21/210 = 179/210
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