Add 21/24 and 15/42
21/24 + 15/42 is 69/56.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 24 and 42 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 24 × 7 = 168,
21/24 = 21 × 7/24 × 7 = 147/168 - Likewise, for the 2nd fraction, since 42 × 4 = 168,
15/42 = 15 × 4/42 × 4 = 60/168 - Add the two like fractions:
147/168 + 60/168 = 147 + 60/168 = 207/168 - 207/168 simplified gives 69/56
- So, 21/24 + 15/42 = 69/56
In mixed form: 113/56
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