Add 21/42 and 5/15
21/42 + 5/15 is 5/6.
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,
5/15 = 5 × 14/15 × 14 = 70/210 - Add the two like fractions:
105/210 + 70/210 = 105 + 70/210 = 175/210 - 175/210 simplified gives 5/6
- So, 21/42 + 5/15 = 5/6
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