Answers

Add 28/90 and 72/40

1^st number: 28/90, 2^nd number: 1 32/40

28/90 + 72/40 is 19/9.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 40 is 360
   
   Next, find the equivalent fraction of both fractional numbers with denominator 360
2. For the 1st fraction, since 90 × 4 = 360,
   28/90 = 28 × 4/90 × 4 = 112/360
3. Likewise, for the 2nd fraction, since 40 × 9 = 360,
   72/40 = 72 × 9/40 × 9 = 648/360
4. Add the two like fractions:
   112/360 + 648/360 = 112 + 648/360 = 760/360
5. 760/360 simplified gives 19/9
6. So, 28/90 + 72/40 = 19/9
   In mixed form: 21/9

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