Add 21/12 and 9/45, Solve 1 9/12 + 9/45 as a fraction

Add 21/12 and 9/45

1^st number: 1 9/12, 2^nd number: 9/45

21/12 + 9/45 is 39/20.

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

Next, find the equivalent fraction of both fractional numbers with denominator 180
For the 1st fraction, since 12 × 15 = 180,
21/12 = 21 × 15/12 × 15 = 315/180
Likewise, for the 2nd fraction, since 45 × 4 = 180,
9/45 = 9 × 4/45 × 4 = 36/180
Add the two like fractions:
315/180 + 36/180 = 315 + 36/180 = 351/180
351/180 simplified gives 39/20
So, 21/12 + 9/45 = 39/20
In mixed form: 119/20

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