# Decision Maths AS (Edexcel) Query

Discussion in 'Mathematics' started by tazza, Dec 12, 2017.

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1. ### tazzaNew commenter

I am confused about how or if Floyd's algorithm will be tested explicitly or could be used in the new Decision Maths specification for Edexcel. The official specification just mentions that it will not be used for odd nodes. The supporting book suggests it will be used in some sort of application. Can anyone enlighten me on how it will be used/tested? In the past specifications there was no mention of it at D1 and whilst it could be used to find the shortest route between 2 nodes it wasn't needed to be taught as most could be found by inspection easily enough. Thanks

2. ### LastMinuteMathsNew commenter

It is not part of AS in Edexcel, but it is in A-Level. I’m not sure where you read the bit about odd nodes, but that doesn’t make much difference to the problem. From the spec:

When applying Floyd’s algorithm, unless directed otherwise, students will be expected to complete the first iteration on the first row of the corresponding distance and route problems, the second iteration on the second row and so on until the algorithm is complete.

I created a lesson for Floyd’s, in case helpful:
https://www.tes.com/teaching-resource/floyd-s-algorithm-decision-1-full-lesson-12025899

3. ### MLMathsNew commenter

I checked this last week. No Floyd's Algorithm until A Level. It's not in the AS.

There was some confusion (on my part) since the contents page of our books (Pearson) have a misprint that makes it look like Floyd is part of the AS.

4. ### mariesimmondsNew commenter

Was anyone else completely surprised at the Floyd's question in the 24th June 2019 paper, 5 marks for 3 iterations is rediculous ..... my students said they were working through the whole test and couldn't finish it! I am thinking of complaining any thoughts.

5. ### LastMinuteMathsNew commenter

Hi Marie,

Have you tried the question? I just timed myself doing the question now and the initial route tables and the first three iterations (parts (a) and (b), so 7 marks in total) took me 6 mins 30secs. I'd expect students to work a little slower, but given the numbers are all quite small I don't think it's totally unreasonable, especially as the following three marks awarded in part (c) for using the tables should only take about a minute to pick up.

What is pretty clear from this question is that Edexcel expect students to be able to do these kinds of calculations mentally, so any students relying on their calculators might really struggle for time.