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### History and Feedback

#### Checkpoint description

Describe what's changed since the last checkpoint.

#### Christian Lawson-Perfect2 years, 3 months ago

Gave some feedback: Ready to use

#### Christian Lawson-Perfect2 years, 3 months ago

Saved a checkpoint:

I've tidied up the text, and gone to town on the variables because they were crazy.

Published this.

#### Elliott Fletcher2 years, 4 months ago

I have rearranged this question quite a bit.

I have made it a two part question, instead of just having one part asking you to find the partial sum of the sequence, as the steps would've been too long if it was just a one-part question and i think a lot of students would find this question difficult without some guidance.

The first part asks the student to calculate the term number of the last term of the sequence and then the second part asks the student to calculate the partial sum.

I have also rewritten the statement and the advice accordingly.

#### Elliott Fletcher2 years, 4 months ago

Gave some feedback: Needs to be tested

#### Elliott Fletcher2 years, 4 months ago

Gave some feedback: Has some problems

#### Hannah Aldous2 years, 4 months ago

Gave some feedback: Needs to be tested

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

Gave some feedback: Has some problems

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

Saved a checkpoint:

Fixed a few typos...

You need to show the limits of the sum: $\sum_{i=1}^n$ instead of just $\sum$.

There are a couple of steps you need to carry out in order to work out the partial sum given a list of the elements:

• Identify $a_1$ and $a_n$.
• Calculate $n$.

These could be in Steps, to guide students through the calculation.

Similarly in part b), you need to identify the first term and common difference; these could be Steps.

You've put i) and ii) in the advice, but not in the question itself! And they're basically the same question, aren't they?

The advice uses $d$ for the common difference, but never introduces it. And if your first term is $a_0$ instead of $a_1$, the formula for $a_n$ is a lot nicer.

I don't like "We need to find the difference between $20 \rightarrow 30 \rightarrow 40$". That's not a sentence! I'd prefer something like "We need to find $d$, the common difference between consecutive terms in the sequence."

This could be split into two separate questions.

#### Hannah Aldous2 years, 4 months ago

Gave some feedback: Needs to be tested

#### Hannah Aldous2 years, 5 months ago

Created this as a copy of Arithmetic sequences in an ice cream shop.
Arithmetic sequences in an ice cream shop Ready to use Hannah Aldous 01/08/2017 13:41
Compute the partial sum of an arithmetic sequence Ready to use Hannah Aldous 01/08/2017 13:32
Finding the $n^{\text{th}}$ Term of a Quadratic Sequence Ready to use Hannah Aldous 01/08/2017 13:28
Identifying different types of sequences Ready to use Hannah Aldous 14/05/2019 14:52
Finding the formula for the $n^{\text{th}}$ term of linear sequences Ready to use Hannah Aldous 01/08/2017 13:40
Partial sum of an arithmetic sequence - birthday money Ready to use Hannah Aldous 01/08/2017 13:45
Find common difference in arithmetic sequences with gaps Ready to use Christian Lawson-Perfect 01/08/2017 13:56
Fill in the gaps in an arithmetic sequence Ready to use Christian Lawson-Perfect 01/08/2017 13:57
Write down and apply the formula for an arithmetic sequence. Ready to use Christian Lawson-Perfect 01/08/2017 13:57
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 01/08/2017 13:31
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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