Subtract 20/70 from 4/21
4/21 - 20/70 is -2/21.
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,
4/21 = 4 × 10/21 × 10 = 40/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
20/70 = 20 × 3/70 × 3 = 60/210 - Subtract the two like fractions:
40/210 - 60/210 = 40 - 60/210 = -20/210 - After reducing the fraction, the answer is -2/21
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