Add 40/21 and 21/20, Solve 1 19/21 + 1 1/20 as a fraction

Add 40/21 and 21/20

1^st number: 1 19/21, 2^nd number: 1 1/20

40/21 + 21/20 is 1241/420.

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,
40/21 = 40 × 20/21 × 20 = 800/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
21/20 = 21 × 21/20 × 21 = 441/420
Add the two like fractions:
800/420 + 441/420 = 800 + 441/420 = 1241/420
So, 40/21 + 21/20 = 1241/420
In mixed form: 2401/420

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