Subtract 21/20 from 18/7
1st number: 2 4/7, 2nd number: 1 1/20
18/7 - 21/20 is 213/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 7 × 20 = 140,
18/7 = 18 × 20/7 × 20 = 360/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
21/20 = 21 × 7/20 × 7 = 147/140 - Subtract the two like fractions:
360/140 - 147/140 = 360 - 147/140 = 213/140 - In mixed form: 173/140
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