Add 30/21 and 18/90, Solve 1 9/21 + 18/90 as a fraction

Add 30/21 and 18/90

1^st number: 1 9/21, 2^nd number: 18/90

30/21 + 18/90 is 57/35.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 21 × 30 = 630,
30/21 = 30 × 30/21 × 30 = 900/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
18/90 = 18 × 7/90 × 7 = 126/630
Add the two like fractions:
900/630 + 126/630 = 900 + 126/630 = 1026/630
1026/630 simplified gives 57/35
So, 30/21 + 18/90 = 57/35
In mixed form: 122/35

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