Answers

Subtract 21/54 from 42/90

42/90 - 21/54 is 7/90.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 54 is 270
   
   Next, find the equivalent fraction of both fractional numbers with denominator 270
2. For the 1st fraction, since 90 × 3 = 270,
   42/90 = 42 × 3/90 × 3 = 126/270
3. Likewise, for the 2nd fraction, since 54 × 5 = 270,
   21/54 = 21 × 5/54 × 5 = 105/270
4. Subtract the two like fractions:
   126/270 - 105/270 = 126 - 105/270 = 21/270
5. After reducing the fraction, the answer is 7/90

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