Add 21/45 and 12/20
21/45 + 12/20 is 16/15.
Steps for adding fractions
- 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,
12/20 = 12 × 9/20 × 9 = 108/180 - Add the two like fractions:
84/180 + 108/180 = 84 + 108/180 = 192/180 - 192/180 simplified gives 16/15
- So, 21/45 + 12/20 = 16/15
In mixed form: 11/15
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