Add 21/42 and 8/15
21/42 + 8/15 is 31/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 15 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
8/15 = 8 × 14/15 × 14 = 112/210 - Add the two like fractions:
105/210 + 112/210 = 105 + 112/210 = 217/210 - 217/210 simplified gives 31/30
- So, 21/42 + 8/15 = 31/30
In mixed form: 11/30
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