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Hi John,
If mean is 150 standard deviation is 20 how to find z score without value of x ..
Answer says it’s .84Please do check that you have typed out. the whole of the question correctly because on what you have typed it is not possible.
If it is from the BPP Revision Kit then please tell me which question and then I can check for myself 🙂
Also John , i am seeing so mnay times in bpp about calculating z score of upper quartile ..
upper quartile is 25% . everywhere they say from the table the z score us 0.67
i cant get my head around itI am now away from home until late tomorrow night and do not have the Revision Kit with me.
Please ask again on Tuesday and I will answer you then.Hi John, Q 4b19 from BPP
Also 4b18 , where they are asking about upperquartile.
In a normal distribution of the upper quartile 3rd or 4th ?
I don’t also understand how they decided there are 0.67 standard deviationshey! I have just started preparing for acca nd beginning with f1. So can you tell me that the notes from opentution are sufficient for the exam purpose ? Also can you describe how the initial exams are(difficulty level)
brahmjot12: Paper F1 is now called Paper AB, so please do not keep posting the same question in irrelevant forums – either ask in the general ACCA forum or in the Paper AB forum.
Q 4b.19 is not as you originally typed it!!!
50% of the distribution is below the mean, therefore there must be 30% between the mean and the limit that we are after.
So you need to work backwards in the tables (as I show in my lectures) to find what z-score gives an answer of 0.30. The closest is a z-score of 0.84 (which gives a probability of 0.2995)Q4b 18
The upper quartile is the top 25%, so the limit required is the figure for which 75% of the observations lie below.
It is then the same workings as for 4b19, except that it is 75% and not 80%.
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