Subtract 10/21 from 7/70
7/70 - 10/21 is -79/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
7/70 = 7 × 3/70 × 3 = 21/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
10/21 = 10 × 10/21 × 10 = 100/210 - Subtract the two like fractions:
21/210 - 100/210 = 21 - 100/210 = -79/210
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