Forums › Ask CIMA Tutor Forums › Ask CIMA P1 Tutor Forums › Decision Tree Question
- This topic has 3 replies, 2 voices, and was last updated 7 years ago by Cath.
- AuthorPosts
- December 10, 2016 at 11:45 am #363044
Usually find decision trees quite easy, however I can’t reconcile the answer on the Pearson P1 mock test (hoping you could help)…
A company is considering whether to develop and market a new product. Cost of developing is estimated to be $200,000. There is 60% probability that development will succeed and 40% that development will be unsuccessful, and the development costs will be lost.
If development is successful, the product will be marketed. There is 50% chance marketing will be successful, and product will make profit of $250,000. There is 30% chance marketing will be reasonably successful and product will make profit of $150,000, and 20% chance marketing will be unsuccessful, making a loss of $80,000. The profit and loss figures are after taking account of the development costs of $200,000.
The expected value to develop and market the product is:
Answer is $12,400 according to the mock.
My workings so far are (60% x $200,000) – (40% x $200,000) = $40,000
and (0.5 x $250,000) + (0.3 x $150,000) – (0.2 x 80,000) = $154,000
December 10, 2016 at 2:17 pm #363090Hi,
Yes right – its a tricky one.The problem to usual method has been caused because the profit and loss figures relating to developing and marketing already have the costs of developing ( $200,000 deducted from them.).
This cost of $200,000 is not a probability – its a certainty – if we go ahead ( even if we fail) so its wrong to include this cost in the figures when you are doing the below analysis.
(0.5 x $250,000) + (0.3 x $150,000) – (0.2 x 80,000) = $154,000Instead we can add the 200k back to those profit figures so that you have
(0.5 x 450,000) + (0.3 x $350,000) + (0.2 x 120,000) = $354,000
$354,000 is the expected value of the marketing results before the cost of development is deducted.
We have a 60% chance of getting to that point ( i.e. only if the development succeeds)
0.6 x 354000 = $212400Then we take off the cost of development which is a certainty of $200,000 – leaving us with expected value of $12,400.
We ignore the 40% chance of failure because the question only asks what is the expected value of developing AND marketing the product – so just the value of one branch.
Hope this helps
Kind Regards
CathDecember 10, 2016 at 4:32 pm #363136Thanks very much, this really helps.
December 12, 2016 at 12:38 am #363320You’re welcome
- AuthorPosts
- You must be logged in to reply to this topic.