Add 5/4 and 75/21, Solve 1 1/4 + 3 12/21 as a fraction

Add 5/4 and 75/21

1^st number: 1 1/4, 2^nd number: 3 12/21

5/4 + 75/21 is 135/28.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 4 × 21 = 84,
5/4 = 5 × 21/4 × 21 = 105/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
75/21 = 75 × 4/21 × 4 = 300/84
Add the two like fractions:
105/84 + 300/84 = 105 + 300/84 = 405/84
405/84 simplified gives 135/28
So, 5/4 + 75/21 = 135/28
In mixed form: 423/28

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