Add 24/21 and 35/20, Solve 1 3/21 + 1 15/20 as a fraction

Add 24/21 and 35/20

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

24/21 + 35/20 is 81/28.

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

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 21 × 20 = 420,
24/21 = 24 × 20/21 × 20 = 480/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
35/20 = 35 × 21/20 × 21 = 735/420
Add the two like fractions:
480/420 + 735/420 = 480 + 735/420 = 1215/420
1215/420 simplified gives 81/28
So, 24/21 + 35/20 = 81/28
In mixed form: 225/28

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