Subtract 4/90 from 21/36
21/36 - 4/90 is 97/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 90 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 90 × 2 = 180,
4/90 = 4 × 2/90 × 2 = 8/180 - Subtract the two like fractions:
105/180 - 8/180 = 105 - 8/180 = 97/180
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