Add 8/15 and 20/21
8/15 + 20/21 is 52/35.
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,
8/15 = 8 × 7/15 × 7 = 56/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
20/21 = 20 × 5/21 × 5 = 100/105 - Add the two like fractions:
56/105 + 100/105 = 56 + 100/105 = 156/105 - 156/105 simplified gives 52/35
- So, 8/15 + 20/21 = 52/35
In mixed form: 117/35
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