Add 15/21 and 20/35
15/21 + 20/35 is 9/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 35 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
15/21 = 15 × 5/21 × 5 = 75/105 - Likewise, for the 2nd fraction, since 35 × 3 = 105,
20/35 = 20 × 3/35 × 3 = 60/105 - Add the two like fractions:
75/105 + 60/105 = 75 + 60/105 = 135/105 - 135/105 simplified gives 9/7
- So, 15/21 + 20/35 = 9/7
In mixed form: 12/7
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