Subtract 21/18 from 4/5
1st number: 4/5, 2nd number: 1 3/18
4/5 - 21/18 is -11/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 5 × 18 = 90,
4/5 = 4 × 18/5 × 18 = 72/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
21/18 = 21 × 5/18 × 5 = 105/90 - Subtract the two like fractions:
72/90 - 105/90 = 72 - 105/90 = -33/90 - After reducing the fraction, the answer is -11/30
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