Add 3/20 and 36/21, Solve 3/20 + 1 15/21 as a fraction

Add 3/20 and 36/21

1^st number: 3/20, 2^nd number: 1 15/21

3/20 + 36/21 is 261/140.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
3/20 = 3 × 21/20 × 21 = 63/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
36/21 = 36 × 20/21 × 20 = 720/420
Add the two like fractions:
63/420 + 720/420 = 63 + 720/420 = 783/420
783/420 simplified gives 261/140
So, 3/20 + 36/21 = 261/140
In mixed form: 1121/140

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