Subtract 20/18 from 21/8
1st number: 2 5/8, 2nd number: 1 2/18
21/8 - 20/18 is 109/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 18 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 8 × 9 = 72,
21/8 = 21 × 9/8 × 9 = 189/72 - Likewise, for the 2nd fraction, since 18 × 4 = 72,
20/18 = 20 × 4/18 × 4 = 80/72 - Subtract the two like fractions:
189/72 - 80/72 = 189 - 80/72 = 109/72 - In mixed form: 137/72
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