Answers

Add 90/72 and 45/20

1^st number: 1 18/72, 2^nd number: 2 5/20

90/72 + 45/20 is 7/2.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 72 and 20 is 360
   
   Next, find the equivalent fraction of both fractional numbers with denominator 360
2. For the 1st fraction, since 72 × 5 = 360,
   90/72 = 90 × 5/72 × 5 = 450/360
3. Likewise, for the 2nd fraction, since 20 × 18 = 360,
   45/20 = 45 × 18/20 × 18 = 810/360
4. Add the two like fractions:
   450/360 + 810/360 = 450 + 810/360 = 1260/360
5. 1260/360 simplified gives 7/2
6. So, 90/72 + 45/20 = 7/2
   In mixed form: 31/2

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