A company produces units with an average length of 10 cm, and a standard deviation of 0.2 cm. There is a 0.95 (or 95%) probability that the length will be more than X cms. Calculate the value for X.
Why are you attempting a question for which you do not have an answer? You should be using a Revision Kit from one of the ACCA Approved Publishers – it has answers and workings 🙂
If you watch my free lectures on the normal distribution you will see that I work through exactly the same example as you have typed out, and explain what to do!!
The lectures are a complete free course for Paper MA and cover everything needed to be able to pass the exam well.