Add 30/45 and 4/42, Solve 30/45 + 4/42 as a fraction

Add 30/45 and 4/42

30/45 + 4/42 is 16/21.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 42 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 45 × 14 = 630,
30/45 = 30 × 14/45 × 14 = 420/630
Likewise, for the 2nd fraction, since 42 × 15 = 630,
4/42 = 4 × 15/42 × 15 = 60/630
Add the two like fractions:
420/630 + 60/630 = 420 + 60/630 = 480/630
480/630 simplified gives 16/21
So, 30/45 + 4/42 = 16/21

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