Add 5/15 and 2/21
5/15 + 2/21 is 3/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
5/15 = 5 × 7/15 × 7 = 35/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
2/21 = 2 × 5/21 × 5 = 10/105 - Add the two like fractions:
35/105 + 10/105 = 35 + 10/105 = 45/105 - 45/105 simplified gives 3/7
- So, 5/15 + 2/21 = 3/7
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