Add 75/21 and 5/20, Solve 3 12/21 + 5/20 as a fraction

Add 75/21 and 5/20

1^st number: 3 12/21, 2^nd number: 5/20

75/21 + 5/20 is 107/28.

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,
75/21 = 75 × 20/21 × 20 = 1500/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
5/20 = 5 × 21/20 × 21 = 105/420
Add the two like fractions:
1500/420 + 105/420 = 1500 + 105/420 = 1605/420
1605/420 simplified gives 107/28
So, 75/21 + 5/20 = 107/28
In mixed form: 323/28

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