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### History and Feedback

#### Checkpoint description

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#### Christian Lawson-Perfect2 years, 4 months ago

Gave some feedback: Ready to use

#### Christian Lawson-Perfect2 years, 4 months ago

Saved a checkpoint:

Lots of little edits - I basically disagreed with every formatting choice you made!

This is a good question.

#### Elliott Fletcher2 years, 4 months ago

Gave some feedback: Needs to be tested

#### Chris Graham2 years, 4 months ago

Gave some feedback: Has some problems

#### Chris Graham2 years, 4 months ago

Ok, so we'e basically torn up and re-written the original question... This looks good, however as for previous questions on arithmetic series, can we have a table of the values and differences in the advice to part (a) please.

I would change "by his" in the statement to "after his", as it implies the amount before he receives money on his birthday. I know that you state that it includes the amount after, but this appears contradictory.

I'm not keen on $n$ being "the amount of numbers in a sequence". So if you have 10 terms in the sequence but you're calculating the $a_5$ term, do you still use $n=10$? "Term number" is terminology that is often used.

#### Chris Graham2 years, 4 months ago

Sorry, you are quite right, I meant to say interest! If you are wording the question in a way that it is "What contribution...?" then you don't really need this anyway, so I have removed those references.

Published this.

#### Elliott Fletcher2 years, 4 months ago

Gave some feedback: Needs to be tested

#### Elliott Fletcher2 years, 4 months ago

Is inflation the right term that we need or should it be interest?

#### Chris Graham2 years, 4 months ago

As discussed, the sum of candles on a birthday cake over several years makes little sense either. Why would you want to know?

Parents adding money to a bank account is much better, and then you could ask (excluding inflation) how much money the parents have added over $n$ years.

This can also be split into two parts, firstly calculate $a_n$ for the given $n$, and then the sum of the series, with a step for each part.

#### Chris Graham2 years, 4 months ago

The step doesn't give enough useful information, and neither does it give the opportunity for the student to break down the question: so the first step would be to find $a_n$, but the step doesn't tell me how to do that. There's an easy opportunity to have gaps here for the common difference, the final term, and so on.

I also have major issues with the context. I'm led to believe Bruce receives 93 slices of his birthday cake on his 50th birthday. How big are these slices? I can only assume that they are getting smaller at a rate inversely proportional to the increase in slices. How about changing to the number of candles? 93 candles on a cake is still a stretch, but slightly more plausible.

#### Chris Graham2 years, 4 months ago

Gave some feedback: Has some problems

#### Hannah Aldous2 years, 5 months ago

Gave some feedback: Needs to be tested

#### Hannah Aldous2 years, 5 months ago

Created this as a copy of Compute the partial sum of an arithmetic sequence.
Arithmetic sequences in an ice cream shop Ready to use Hannah Aldous 20/11/2019 14:36
Compute the partial sum of an arithmetic sequence Ready to use Hannah Aldous 20/11/2019 14:36
Finding the $n^{\text{th}}$ Term of a Quadratic Sequence Ready to use Hannah Aldous 20/11/2019 14:39
Identifying different types of sequences Ready to use Hannah Aldous 20/11/2019 14:40
Finding the formula for the $n^{\text{th}}$ term of linear sequences Ready to use Hannah Aldous 20/11/2019 14:39
Partial sum of an arithmetic sequence - birthday money Ready to use Hannah Aldous 20/11/2019 14:41
Find common difference in arithmetic sequences with gaps Ready to use Christian Lawson-Perfect 20/11/2019 14:39
Fill in the gaps in an arithmetic sequence Ready to use Christian Lawson-Perfect 20/11/2019 14:39
Write down and apply the formula for an arithmetic sequence. Ready to use Christian Lawson-Perfect 20/11/2019 14:46
Finding the Formula for the $n^{\text{th}}$ Term of Linear Sequences draft Chris Graham 20/07/2017 15:08
Inbbavathie's copy of Find common difference in arithmetic sequences with gaps draft Inbbavathie Ravi 24/07/2017 03:48
Find a particular term of a sequence using the given formula Ready to use Christian Lawson-Perfect 20/11/2019 14:38
Johan's copy of Write down and apply the formula for an arithmetic sequence. Has some problems Johan Maertens 02/08/2017 17:51
Finding the formula for the $n^{\text{th}}$ term of linear sequences draft steve kilgallon 19/11/2017 08:09
Compute the partial sum of an arithmetic sequence draft steve kilgallon 19/11/2017 08:11
Identifying different types of sequences draft Luis Hernandez 31/12/2018 01:38
Calcular la suma parcial de una sucesión aritmética Ready to use Luis Hernandez 14/01/2019 17:37
Identificando diferentes tipos de secuencias Ready to use Luis Hernandez 14/01/2019 13:19
Suma parcial de una secuencia aritmética - Cumpleaños Ready to use Luis Hernandez 14/01/2019 19:01
Encontrar la diferencia común en una Secuencia Aritmética Ready to use Luis Hernandez 14/01/2019 17:40
Encuentra un término particular de una secuencia usando la fórmula dada Ready to use Luis Hernandez 14/01/2019 17:48
Encontrar la fórmula para el término $n^{\text {th}}$ de una secuencia lineal Ready to use Luis Hernandez 14/01/2019 19:29
Simon's copy of Write down and apply the formula for an arithmetic sequence. draft Simon Thomas 25/02/2019 10:20
Simon's copy of Find common difference in arithmetic sequences with gaps draft Simon Thomas 25/02/2019 10:24
Simon's copy of Finding the formula for the $n^{\text{th}}$ term of linear sequences draft Simon Thomas 25/02/2019 10:30
Identifying different types of sequences draft Xiaodan Leng 10/07/2019 21:48
Write down and apply the formula for an arithmetic sequence. draft Xiaodan Leng 11/07/2019 01:48
Fill in the gaps in an arithmetic sequence draft Xiaodan Leng 11/07/2019 01:48
Find common difference in arithmetic sequences with gaps draft Xiaodan Leng 11/07/2019 01:49
Compute the partial sum of an arithmetic sequence draft Xiaodan Leng 11/07/2019 01:51
Partial sum of an arithmetic sequence - birthday money draft Xiaodan Leng 11/07/2019 01:54
Arithmetic sequences in an ice cream shop draft Xiaodan Leng 11/07/2019 01:55
Finding the formula for the $n^{\text{th}}$ term of linear sequences draft Xiaodan Leng 11/07/2019 01:55
Find a particular term of a sequence using the given formula draft Xiaodan Leng 11/07/2019 01:56
Finding the $n^{\text{th}}$ Term of a Quadratic Sequence draft Xiaodan Leng 11/07/2019 01:57
Paul's copy of Inbbavathie's copy of Find common difference in arithmetic sequences with gaps draft Paul Verheyen 05/10/2019 09:39

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