Add 21/45 and 7/12
21/45 + 7/12 is 21/20.
Steps for adding fractions
- 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,
7/12 = 7 × 15/12 × 15 = 105/180 - Add the two like fractions:
84/180 + 105/180 = 84 + 105/180 = 189/180 - 189/180 simplified gives 21/20
- So, 21/45 + 7/12 = 21/20
In mixed form: 11/20
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