Add 5/4 and 15/84, Solve 1 1/4 + 15/84 as a fraction

Add 5/4 and 15/84

1^st number: 1 1/4, 2^nd number: 15/84

5/4 + 15/84 is 10/7.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 84 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 84 × 1 = 84,
15/84 = 15 × 1/84 × 1 = 15/84
Add the two like fractions:
105/84 + 15/84 = 105 + 15/84 = 120/84
120/84 simplified gives 10/7
So, 5/4 + 15/84 = 10/7
In mixed form: 13/7

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