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Help with #5 please!!!!!

Help with #5 please!!!!!-example-1
User Amal Kumar S
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1 Answer

21 votes
21 votes

Answer: Choice A

Step-by-step explanation:

Notice how the numerators (2,4,6,8) are multiples of 2. So we can say that they are of the form 2k, where k is a whole number from 1 to 4.

If k = 1, then 2k = 2*1 = 2

If k = 2, then 2k = 2*2 = 4

and so on until we reach k = 4 and 2k = 8.

Similarly, the denominators are also multiples of 2. We shift things 1 spot to the right. So we start with 4 instead of 2. So we need to add on 2

If k = 1, then 2k+2 = 2*1+2 = 4

If k = 2, then 2k+2 = 2*2+2 = 6

and so on.


\displaystyle \sum_(k=1)^(4)(2k)/(2k+2) = (2)/(4)+(4)/(6)+(6)/(8)+(8)/(10)

User Hot Zellah
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