Answers

Subtract 42/45 from 81/4

1^st number: 20 1/4, 2^nd number: 42/45

81/4 - 42/45 is 1159/60.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 4 and 45 is 180
   
   Next, find the equivalent fraction of both fractional numbers with denominator 180
2. For the 1st fraction, since 4 × 45 = 180,
   81/4 = 81 × 45/4 × 45 = 3645/180
3. Likewise, for the 2nd fraction, since 45 × 4 = 180,
   42/45 = 42 × 4/45 × 4 = 168/180
4. Subtract the two like fractions:
   3645/180 - 168/180 = 3645 - 168/180 = 3477/180
5. After reducing the fraction, the answer is 1159/60
6. In mixed form: 1919/60

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