Add 20/40 and 42/80, Solve 20/40 + 42/80 as a fraction

Add 20/40 and 42/80

20/40 + 42/80 is 41/40.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 80 is 80

Next, find the equivalent fraction of both fractional numbers with denominator 80
For the 1st fraction, since 40 × 2 = 80,
20/40 = 20 × 2/40 × 2 = 40/80
Likewise, for the 2nd fraction, since 80 × 1 = 80,
42/80 = 42 × 1/80 × 1 = 42/80
Add the two like fractions:
40/80 + 42/80 = 40 + 42/80 = 82/80
82/80 simplified gives 41/40
So, 20/40 + 42/80 = 41/40
In mixed form: 11/40

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