Add 30/21 and 80/45, Solve 1 9/21 + 1 35/45 as a fraction

Add 30/21 and 80/45

1^st number: 1 9/21, 2^nd number: 1 35/45

30/21 + 80/45 is 202/63.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 21 × 15 = 315,
30/21 = 30 × 15/21 × 15 = 450/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
80/45 = 80 × 7/45 × 7 = 560/315
Add the two like fractions:
450/315 + 560/315 = 450 + 560/315 = 1010/315
1010/315 simplified gives 202/63
So, 30/21 + 80/45 = 202/63
In mixed form: 313/63

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