Subtract 18/7 from 21/70
1st number: 21/70, 2nd number: 2 4/7
21/70 - 18/7 is -159/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 7 is 70
Next, find the equivalent fraction of both fractional numbers with denominator 70 - For the 1st fraction, since 70 × 1 = 70,
21/70 = 21 × 1/70 × 1 = 21/70 - Likewise, for the 2nd fraction, since 7 × 10 = 70,
18/7 = 18 × 10/7 × 10 = 180/70 - Subtract the two like fractions:
21/70 - 180/70 = 21 - 180/70 = -159/70
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