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

Add 18/90 and 30/21

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

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

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

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

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