Add 40/42 and 90/54, Solve 40/42 + 1 36/54 as a fraction

Add 40/42 and 90/54

1^st number: 40/42, 2^nd number: 1 36/54

40/42 + 90/54 is 55/21.

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,
90/54 = 90 × 7/54 × 7 = 630/378
Add the two like fractions:
360/378 + 630/378 = 360 + 630/378 = 990/378
990/378 simplified gives 55/21
So, 40/42 + 90/54 = 55/21
In mixed form: 213/21

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