Subtract 20/18 from 21/4
1st number: 5 1/4, 2nd number: 1 2/18
21/4 - 20/18 is 149/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 18 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 4 × 9 = 36,
21/4 = 21 × 9/4 × 9 = 189/36 - Likewise, for the 2nd fraction, since 18 × 2 = 36,
20/18 = 20 × 2/18 × 2 = 40/36 - Subtract the two like fractions:
189/36 - 40/36 = 189 - 40/36 = 149/36 - In mixed form: 45/36
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