Add 21/45 and 45/20, Solve 21/45 + 2 5/20 as a fraction

Add 21/45 and 45/20

1^st number: 21/45, 2^nd number: 2 5/20

21/45 + 45/20 is 163/60.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 20 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 20 × 9 = 180,
45/20 = 45 × 9/20 × 9 = 405/180
Add the two like fractions:
84/180 + 405/180 = 84 + 405/180 = 489/180
489/180 simplified gives 163/60
So, 21/45 + 45/20 = 163/60
In mixed form: 243/60

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