Answers

Add 90/20 and 42/56

1^st number: 4 10/20, 2^nd number: 42/56

90/20 + 42/56 is 21/4.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 56 is 280
   
   Next, find the equivalent fraction of both fractional numbers with denominator 280
2. For the 1st fraction, since 20 × 14 = 280,
   90/20 = 90 × 14/20 × 14 = 1260/280
3. Likewise, for the 2nd fraction, since 56 × 5 = 280,
   42/56 = 42 × 5/56 × 5 = 210/280
4. Add the two like fractions:
   1260/280 + 210/280 = 1260 + 210/280 = 1470/280
5. 1470/280 simplified gives 21/4
6. So, 90/20 + 42/56 = 21/4
   In mixed form: 51/4

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