Add 7/21 and 8/15
7/21 + 8/15 is 13/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
7/21 = 7 × 5/21 × 5 = 35/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
8/15 = 8 × 7/15 × 7 = 56/105 - Add the two like fractions:
35/105 + 56/105 = 35 + 56/105 = 91/105 - 91/105 simplified gives 13/15
- So, 7/21 + 8/15 = 13/15
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