Add 21/4 and 45/18, Solve 5 1/4 + 2 9/18 as a fraction

Add 21/4 and 45/18

1^st number: 5 1/4, 2^nd number: 2 9/18

21/4 + 45/18 is 31/4.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 18 is 36

Next, find the equivalent fraction of both fractional numbers with denominator 36
For the 1st fraction, since 4 × 9 = 36,
21/4 = 21 × 9/4 × 9 = 189/36
Likewise, for the 2nd fraction, since 18 × 2 = 36,
45/18 = 45 × 2/18 × 2 = 90/36
Add the two like fractions:
189/36 + 90/36 = 189 + 90/36 = 279/36
279/36 simplified gives 31/4
So, 21/4 + 45/18 = 31/4
In mixed form: 73/4

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