Subtract 21/54 from 42/45
42/45 - 21/54 is 49/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 54 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 45 × 6 = 270,
42/45 = 42 × 6/45 × 6 = 252/270 - Likewise, for the 2nd fraction, since 54 × 5 = 270,
21/54 = 21 × 5/54 × 5 = 105/270 - Subtract the two like fractions:
252/270 - 105/270 = 252 - 105/270 = 147/270 - After reducing the fraction, the answer is 49/90
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