Subtract 4/70 from 18/21
18/21 - 4/70 is 4/5.
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,
18/21 = 18 × 10/21 × 10 = 180/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
4/70 = 4 × 3/70 × 3 = 12/210 - Subtract the two like fractions:
180/210 - 12/210 = 180 - 12/210 = 168/210 - After reducing the fraction, the answer is 4/5
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