Add 15/2 and 21/84, Solve 7 1/2 + 21/84 as a fraction

Add 15/2 and 21/84

1^st number: 7 1/2, 2^nd number: 21/84

15/2 + 21/84 is 31/4.

Find the least common denominator or LCM of the two denominators:
LCM of 2 and 84 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 2 × 42 = 84,
15/2 = 15 × 42/2 × 42 = 630/84
Likewise, for the 2nd fraction, since 84 × 1 = 84,
21/84 = 21 × 1/84 × 1 = 21/84
Add the two like fractions:
630/84 + 21/84 = 630 + 21/84 = 651/84
651/84 simplified gives 31/4
So, 15/2 + 21/84 = 31/4
In mixed form: 73/4

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