Subtract 21/70 from 18/7
1st number: 2 4/7, 2nd number: 21/70
18/7 - 21/70 is 159/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 70 is 70
Next, find the equivalent fraction of both fractional numbers with denominator 70 - For the 1st fraction, since 7 × 10 = 70,
18/7 = 18 × 10/7 × 10 = 180/70 - Likewise, for the 2nd fraction, since 70 × 1 = 70,
21/70 = 21 × 1/70 × 1 = 21/70 - Subtract the two like fractions:
180/70 - 21/70 = 180 - 21/70 = 159/70 - In mixed form: 219/70
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