Add 21/42 and 15/24
21/42 + 15/24 is 9/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 24 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 42 × 4 = 168,
21/42 = 21 × 4/42 × 4 = 84/168 - Likewise, for the 2nd fraction, since 24 × 7 = 168,
15/24 = 15 × 7/24 × 7 = 105/168 - Add the two like fractions:
84/168 + 105/168 = 84 + 105/168 = 189/168 - 189/168 simplified gives 9/8
- So, 21/42 + 15/24 = 9/8
In mixed form: 11/8
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