Add 5/4 and 35/21, Solve 1 1/4 + 1 14/21 as a fraction

Add 5/4 and 35/21

1^st number: 1 1/4, 2^nd number: 1 14/21

5/4 + 35/21 is 35/12.

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,
35/21 = 35 × 4/21 × 4 = 140/84
Add the two like fractions:
105/84 + 140/84 = 105 + 140/84 = 245/84
245/84 simplified gives 35/12
So, 5/4 + 35/21 = 35/12
In mixed form: 211/12

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