Add 21/4 and 27/45, Solve 5 1/4 + 27/45 as a fraction

Add 21/4 and 27/45

1^st number: 5 1/4, 2^nd number: 27/45

21/4 + 27/45 is 117/20.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 45 is 180

Next, find the equivalent fraction of both fractional numbers with denominator 180
For the 1st fraction, since 4 × 45 = 180,
21/4 = 21 × 45/4 × 45 = 945/180
Likewise, for the 2nd fraction, since 45 × 4 = 180,
27/45 = 27 × 4/45 × 4 = 108/180
Add the two like fractions:
945/180 + 108/180 = 945 + 108/180 = 1053/180
1053/180 simplified gives 117/20
So, 21/4 + 27/45 = 117/20
In mixed form: 517/20

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