Add 21/45 and 18/12, Solve 21/45 + 1 6/12 as a fraction

Add 21/45 and 18/12

1^st number: 21/45, 2^nd number: 1 6/12

21/45 + 18/12 is 59/30.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 12 is 180

Next, find the equivalent fraction of both fractional numbers with denominator 180
For the 1st fraction, since 45 × 4 = 180,
21/45 = 21 × 4/45 × 4 = 84/180
Likewise, for the 2nd fraction, since 12 × 15 = 180,
18/12 = 18 × 15/12 × 15 = 270/180
Add the two like fractions:
84/180 + 270/180 = 84 + 270/180 = 354/180
354/180 simplified gives 59/30
So, 21/45 + 18/12 = 59/30
In mixed form: 129/30

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