I'm sorry for asking a maths question again. XD
Q8. The smallest 84% of stainless steel nails are less than 49.7mm long, and the largest 97.5% are longer than 41.6mm long.
a. Caculate the likely mean length of the nails and an appropriate value for the standard deviation.
What do I do? >.<
Thanks in advance! =]
There are many on-line calculators that can do it for you. For example:
z score Calculator