Answers

Add 90/21 and 90/30

1^st number: 4 6/21, 2^nd number: 3 0/30

90/21 + 90/30 is 51/7.

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,
   90/21 = 90 × 10/21 × 10 = 900/210
3. Likewise, for the 2nd fraction, since 30 × 7 = 210,
   90/30 = 90 × 7/30 × 7 = 630/210
4. Add the two like fractions:
   900/210 + 630/210 = 900 + 630/210 = 1530/210
5. 1530/210 simplified gives 51/7
6. So, 90/21 + 90/30 = 51/7
   In mixed form: 72/7

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