The head of a business school claims that the average MBA graduate is offered a starting salary of $55,000. The standard deviation of the offers is $4,600.
a) What is the probability that in a random sample of 38 MBA graduates, the mean starting salary is less than $53,000?
I am saying that
b) What if only 16 students had been sampled?
This is confusing, can I say
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as is known, can be used for ?
You have to make an underlying assumption of normality at least for the second as you have a small sample and you want to use the t-distribution.
For the first you may get away with relying on the CLT to justify normality, but I would still say I am assuming such (and for that matter also use the t-distribution).
CB