Answers

Add 54/21 and 90/30

1^st number: 2 12/21, 2^nd number: 3 0/30

54/21 + 90/30 is 39/7.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 30 is 210
   
   Next, find the equivalent fraction of both fractional numbers with denominator 210
2. For the 1st fraction, since 21 × 10 = 210,
   54/21 = 54 × 10/21 × 10 = 540/210
3. Likewise, for the 2nd fraction, since 30 × 7 = 210,
   90/30 = 90 × 7/30 × 7 = 630/210
4. Add the two like fractions:
   540/210 + 630/210 = 540 + 630/210 = 1170/210
5. 1170/210 simplified gives 39/7
6. So, 54/21 + 90/30 = 39/7
   In mixed form: 54/7

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