Subtract 21/90 from 4/5
4/5 - 21/90 is 17/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 90 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 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Subtract the two like fractions:
72/90 - 21/90 = 72 - 21/90 = 51/90 - After reducing the fraction, the answer is 17/30
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