Subtract 21/90 from 40/54
40/54 - 21/90 is 137/270.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 90 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 54 × 5 = 270,
40/54 = 40 × 5/54 × 5 = 200/270 - Likewise, for the 2nd fraction, since 90 × 3 = 270,
21/90 = 21 × 3/90 × 3 = 63/270 - Subtract the two like fractions:
200/270 - 63/270 = 200 - 63/270 = 137/270
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