Add 36/80 and 42/21, Solve 36/80 + 2 0/21 as a fraction

Add 36/80 and 42/21

1^st number: 36/80, 2^nd number: 2 0/21

36/80 + 42/21 is 49/20.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 80 × 21 = 1680,
36/80 = 36 × 21/80 × 21 = 756/1680
Likewise, for the 2nd fraction, since 21 × 80 = 1680,
42/21 = 42 × 80/21 × 80 = 3360/1680
Add the two like fractions:
756/1680 + 3360/1680 = 756 + 3360/1680 = 4116/1680
4116/1680 simplified gives 49/20
So, 36/80 + 42/21 = 49/20
In mixed form: 29/20

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