Add 4/20 and 80/21, Solve 4/20 + 3 17/21 as a fraction

Add 4/20 and 80/21

1^st number: 4/20, 2^nd number: 3 17/21

4/20 + 80/21 is 421/105.

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,
4/20 = 4 × 21/20 × 21 = 84/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
80/21 = 80 × 20/21 × 20 = 1600/420
Add the two like fractions:
84/420 + 1600/420 = 84 + 1600/420 = 1684/420
1684/420 simplified gives 421/105
So, 4/20 + 80/21 = 421/105
In mixed form: 41/105

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