Add 42/84 and 40/54, Solve 42/84 + 40/54 as a fraction

Add 42/84 and 40/54

42/84 + 40/54 is 67/54.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 54 is 756

Next, find the equivalent fraction of both fractional numbers with denominator 756
For the 1st fraction, since 84 × 9 = 756,
42/84 = 42 × 9/84 × 9 = 378/756
Likewise, for the 2nd fraction, since 54 × 14 = 756,
40/54 = 40 × 14/54 × 14 = 560/756
Add the two like fractions:
378/756 + 560/756 = 378 + 560/756 = 938/756
938/756 simplified gives 67/54
So, 42/84 + 40/54 = 67/54
In mixed form: 113/54

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