Add 20/40 and 50/21, Solve 20/40 + 2 8/21 as a fraction

Add 20/40 and 50/21

1^st number: 20/40, 2^nd number: 2 8/21

20/40 + 50/21 is 121/42.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 40 × 21 = 840,
20/40 = 20 × 21/40 × 21 = 420/840
Likewise, for the 2nd fraction, since 21 × 40 = 840,
50/21 = 50 × 40/21 × 40 = 2000/840
Add the two like fractions:
420/840 + 2000/840 = 420 + 2000/840 = 2420/840
2420/840 simplified gives 121/42
So, 20/40 + 50/21 = 121/42
In mixed form: 237/42

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