Alpha & Beta errors!

[canon14]

A machine produces 50 lb bags of chips. In this particular process, it is important that the chip content does not go below 49.9 lbs. In fact, when the bags of chips are less than 49.9 lbs, maintenance is performed on the machine. Consider a hypothesis test where:

Ho: X >= 49.9 lbs. (In this case operation is continued)
Ha: X < 49.9 lbs. (In this case maintenance is performed on the machine)

Assume the population standard deviation is 0.5 and the sample size (n) is 100. Calculate the values for a type I error and a type II error. (To calculate Beta, consider a mean that is 1 standard error away from the lower end value to perform maintenance)

My questions are:
1) Don't we need a mean value to calculate alpha & beta?
2) How do I go about assuming a value for Ha, since there is no lower limit defined?

Please help

Thanks
C

[allinorfold]

You have a mean=50.
And just an upper limit is enough for your hypothesis test(upper-tailed)

[canon14]

Ok thanks. I will try it again.

[canon14]

Originally Posted by allinorfold

You have a mean=50.
And just an upper limit is enough for your hypothesis test(upper-tailed)

So is this correct for alpha:

P(alpha) = 1-normdist(9.9,10,std. error,1)

Please advice

Thanks
C