Add 21/12 and 45/18
1st number: 1 9/12, 2nd number: 2 9/18
21/12 + 45/18 is 17/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 18 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 12 × 3 = 36,
21/12 = 21 × 3/12 × 3 = 63/36 - Likewise, for the 2nd fraction, since 18 × 2 = 36,
45/18 = 45 × 2/18 × 2 = 90/36 - Add the two like fractions:
63/36 + 90/36 = 63 + 90/36 = 153/36 - 153/36 simplified gives 17/4
- So, 21/12 + 45/18 = 17/4
In mixed form: 41/4
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