Answers

Subtract 42/90 from 81/40

1^st number: 2 1/40, 2^nd number: 42/90

81/40 - 42/90 is 187/120.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 90 is 360
   
   Next, find the equivalent fraction of both fractional numbers with denominator 360
2. For the 1st fraction, since 40 × 9 = 360,
   81/40 = 81 × 9/40 × 9 = 729/360
3. Likewise, for the 2nd fraction, since 90 × 4 = 360,
   42/90 = 42 × 4/90 × 4 = 168/360
4. Subtract the two like fractions:
   729/360 - 168/360 = 729 - 168/360 = 561/360
5. After reducing the fraction, the answer is 187/120
6. In mixed form: 167/120

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