Subtract 4/5 from 21/36
21/36 - 4/5 is -13/60.
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,
21/36 = 21 × 5/36 × 5 = 105/180 - Likewise, for the 2nd fraction, since 5 × 36 = 180,
4/5 = 4 × 36/5 × 36 = 144/180 - Subtract the two like fractions:
105/180 - 144/180 = 105 - 144/180 = -39/180 - After reducing the fraction, the answer is -13/60
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