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Help with this question

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Original post by Jasminechen
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You just have to model it as an arithmetic sequence.

So for the first peg, he walks a total of 6mm (3mm there and 3mm back)

For the second, he walks a total of 12mm

For the third, he walks a total of 18mm

Can you see what's happening? :smile:
Reply 2
Original post by Indeterminate
You just have to model it as an arithmetic sequence.

So for the first peg, he walks a total of 6mm (3mm there and 3mm back)

For the second, he walks a total of 12mm

For the third, he walks a total of 18mm

Can you see what's happening? :smile:


Yes I substituted it into the equation for Sn with a=0 and d=3 and my final answer is 3675 , is this correct?
I think d=6
Looool. Like the way you circled 'THIS ONE'. Didnt take a look at the question. Sorry

Posted from TSR Mobile
Original post by Jasminechen
Yes I substituted it into the equation for Sn with a=0 and d=3 and my final answer is 3675 , is this correct?


No.

You need to think of it as a sequence of "total distances", i.e where each term is the total distance he walked to put a peg in.
(edited 8 years ago)
Reply 6
Original post by Indeterminate
No.

You need to think of it as a sequence of "total distances", i.e where each term is the total distance he walked to put a peg in.


Do I start from 1 or 6 ?
Original post by Jasminechen
Do I start from 1 or 6 ?


You need to think of it in terms of pegs.

How much does the 1st peg contribute? That's your first term.

How much does the 2nd peg contribute? That's your second term.

etc etc.
Reply 8
Original post by Indeterminate
You need to think of it in terms of pegs.

How much does the 1st peg contribute? That's your first term.

How much does the 2nd peg contribute? That's your second term.

etc etc.


The first peg is put at the foot of the pile hence there was no distance travelled so can a=0 ? And 2nd peg a total of 6m was travelled so 2nd term=6 ?
Original post by Jasminechen
The first peg is put at the foot of the pile hence there was no distance travelled so can a=0 ? And 2nd peg a total of 6m was travelled so 2nd term=6 ?


Correct :smile:
Reply 10
Original post by Indeterminate
Correct :smile:


Thank you 😭!!

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