Add 21/28 and 18/12
1st number: 21/28, 2nd number: 1 6/12
21/28 + 18/12 is 9/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
21/28 = 21 × 3/28 × 3 = 63/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
18/12 = 18 × 7/12 × 7 = 126/84 - Add the two like fractions:
63/84 + 126/84 = 63 + 126/84 = 189/84 - 189/84 simplified gives 9/4
- So, 21/28 + 18/12 = 9/4
In mixed form: 21/4
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