Answers

Subtract 42/80 from 90/54

1^st number: 1 36/54, 2^nd number: 42/80

90/54 - 42/80 is 137/120.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 54 and 80 is 2160
   
   Next, find the equivalent fraction of both fractional numbers with denominator 2160
2. For the 1st fraction, since 54 × 40 = 2160,
   90/54 = 90 × 40/54 × 40 = 3600/2160
3. Likewise, for the 2nd fraction, since 80 × 27 = 2160,
   42/80 = 42 × 27/80 × 27 = 1134/2160
4. Subtract the two like fractions:
   3600/2160 - 1134/2160 = 3600 - 1134/2160 = 2466/2160
5. After reducing the fraction, the answer is 137/120
6. In mixed form: 117/120

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