Add 40/42 and 45/54, Solve 40/42 + 45/54 as a fraction

Add 40/42 and 45/54

40/42 + 45/54 is 25/14.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 54 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 42 × 9 = 378,
40/42 = 40 × 9/42 × 9 = 360/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
45/54 = 45 × 7/54 × 7 = 315/378
Add the two like fractions:
360/378 + 315/378 = 360 + 315/378 = 675/378
675/378 simplified gives 25/14
So, 40/42 + 45/54 = 25/14
In mixed form: 111/14

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