Answers

Add 90/20 and 45/72

1^st number: 4 10/20, 2^nd number: 45/72

90/20 + 45/72 is 41/8.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 72 is 360
   
   Next, find the equivalent fraction of both fractional numbers with denominator 360
2. For the 1st fraction, since 20 × 18 = 360,
   90/20 = 90 × 18/20 × 18 = 1620/360
3. Likewise, for the 2nd fraction, since 72 × 5 = 360,
   45/72 = 45 × 5/72 × 5 = 225/360
4. Add the two like fractions:
   1620/360 + 225/360 = 1620 + 225/360 = 1845/360
5. 1845/360 simplified gives 41/8
6. So, 90/20 + 45/72 = 41/8
   In mixed form: 51/8

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