Add 21/45 and 45/12, Solve 21/45 + 3 9/12 as a fraction

Add 21/45 and 45/12

1^st number: 21/45, 2^nd number: 3 9/12

21/45 + 45/12 is 253/60.

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,
45/12 = 45 × 15/12 × 15 = 675/180
Add the two like fractions:
84/180 + 675/180 = 84 + 675/180 = 759/180
759/180 simplified gives 253/60
So, 21/45 + 45/12 = 253/60
In mixed form: 413/60

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