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Arithmetic sequences increase by the same value in between terms. So term2 - term1 = term3 - term2. Apply that logic to this question and you have an equation in terms of p, then rearrange and solve.
Reply 2


What do you know about arithmetic seqeunces? They have a common difference.

What does the word difference mean? It means the second term minus the first term or the third term minus the second term, etc...

Essentially, the difference between terms have to be the same.

What is the difference between the first two terms in terms of pp?

What is the difference between the third and second term in terms of pp?

Equate them and solve for pp.
Reply 3
Lets say you are given 3 terms: a ar ar^2

The rule that you would apply to find the value of r would be:
ar/a = ar^2/ar
Then you would just solve it for r.

The same rule applies to the values they have given you.

2p/(12-p) = (4p-5)/2p
Solve this to get p. Hope that helps :smile:
Reply 4
Original post by Miningstew
Arithmetic sequences increase by the same value in between terms. So term2 - term1 = term3 - term2. Apply that logic to this question and you have an equation in terms of p, then rearrange and solve.

Thanks a ton
Original post by Zacken
What do you know about arithmetic seqeunces? They have a common difference.

What does the word difference mean? It means the second term minus the first term or the third term minus the second term, etc...

Essentially, the difference between terms have to be the same.

What is the difference between the first two terms in terms of pp?

What is the difference between the third and second term in terms of pp?

Equate them and solve for pp.

Thanks so much i have no idea what i'd do without you guys ^-^
Original post by Filipo
Lets say you are given 3 terms: a ar ar^2

The rule that you would apply to find the value of r would be:
ar/a = ar^2/ar
Then you would just solve it for r.

The same rule applies to the values they have given you.

2p/(12-p) = (4p-5)/2p
Solve this to get p. Hope that helps :smile:


ummm no that's for common ratio's not for sequences which go up by a regular amount
Reply 5
Original post by Filipo
Lets say you are given 3 terms: a ar ar^2

The rule that you would apply to find the value of r would be:
ar/a = ar^2/ar
Then you would just solve it for r.

The same rule applies to the values they have given you.

2p/(12-p) = (4p-5)/2p
Solve this to get p. Hope that helps :smile:


That's a geometric sequence that you're talking about. This is clearly stated as an arithmetic sequence.
Reply 6
Original post by Zacken
That's a geometric sequence that you're talking about. This is clearly stated as an arithmetic sequence.


Oppps, my bad sorry haha
Reply 7
Original post by Filipo
Oppps, my bad sorry haha


Yeah, I've had many a moment too, don't worry. :tongue:
you should get 3p-12 as the difference right?

and then p=7?
(edited 7 years ago)
Reply 9
Original post by richpanda
and then p=7?


Correct.

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