Subtract 21/5 from 18/36
1st number: 18/36, 2nd number: 4 1/5
18/36 - 21/5 is -37/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 5 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 36 × 5 = 180,
18/36 = 18 × 5/36 × 5 = 90/180 - Likewise, for the 2nd fraction, since 5 × 36 = 180,
21/5 = 21 × 36/5 × 36 = 756/180 - Subtract the two like fractions:
90/180 - 756/180 = 90 - 756/180 = -666/180 - After reducing the fraction, the answer is -37/10
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