Add 7/4 and 15/21, Solve 1 3/4 + 15/21 as a fraction

Add 7/4 and 15/21

1^st number: 1 3/4, 2^nd number: 15/21

7/4 + 15/21 is 69/28.

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,
7/4 = 7 × 21/4 × 21 = 147/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
15/21 = 15 × 4/21 × 4 = 60/84
Add the two like fractions:
147/84 + 60/84 = 147 + 60/84 = 207/84
207/84 simplified gives 69/28
So, 7/4 + 15/21 = 69/28
In mixed form: 213/28

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