Add 12/42 and 40/49, Solve 12/42 + 40/49 as a fraction

Add 12/42 and 40/49

12/42 + 40/49 is 54/49.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 49 is 294

Next, find the equivalent fraction of both fractional numbers with denominator 294
For the 1st fraction, since 42 × 7 = 294,
12/42 = 12 × 7/42 × 7 = 84/294
Likewise, for the 2nd fraction, since 49 × 6 = 294,
40/49 = 40 × 6/49 × 6 = 240/294
Add the two like fractions:
84/294 + 240/294 = 84 + 240/294 = 324/294
324/294 simplified gives 54/49
So, 12/42 + 40/49 = 54/49
In mixed form: 15/49

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