Add 5/15 and 18/21
5/15 + 18/21 is 25/21.
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,
18/21 = 18 × 5/21 × 5 = 90/105 - Add the two like fractions:
35/105 + 90/105 = 35 + 90/105 = 125/105 - 125/105 simplified gives 25/21
- So, 5/15 + 18/21 = 25/21
In mixed form: 14/21
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