Subtract 1/90 from 21/27
21/27 - 1/90 is 23/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 90 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 27 × 10 = 270,
21/27 = 21 × 10/27 × 10 = 210/270 - Likewise, for the 2nd fraction, since 90 × 3 = 270,
1/90 = 1 × 3/90 × 3 = 3/270 - Subtract the two like fractions:
210/270 - 3/270 = 210 - 3/270 = 207/270 - After reducing the fraction, the answer is 23/30
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