Add 30/21 and 36/45, Solve 1 9/21 + 36/45 as a fraction

Add 30/21 and 36/45

1^st number: 1 9/21, 2^nd number: 36/45

30/21 + 36/45 is 78/35.

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,
36/45 = 36 × 7/45 × 7 = 252/315
Add the two like fractions:
450/315 + 252/315 = 450 + 252/315 = 702/315
702/315 simplified gives 78/35
So, 30/21 + 36/45 = 78/35
In mixed form: 28/35

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