Add 81/20 and 10/21, Solve 4 1/20 + 10/21 as a fraction

Add 81/20 and 10/21

1^st number: 4 1/20, 2^nd number: 10/21

81/20 + 10/21 is 1901/420.

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,
81/20 = 81 × 21/20 × 21 = 1701/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
10/21 = 10 × 20/21 × 20 = 200/420
Add the two like fractions:
1701/420 + 200/420 = 1701 + 200/420 = 1901/420
So, 81/20 + 10/21 = 1901/420
In mixed form: 4221/420

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