a sample of 16 egg is take froom normal disribution. variance is unknown

sample mean xbar is 4.49 and sample st dev, s, is 1.231

you wish to do a test if the population mean is less than 5

state h0 and h1, calculate test statistic and use the t disribution to find what level you can accept or reject h0.

now i think the h0 is populationmean=5, h1 not equal 5?

test statistic, t=(xbar-5)/(s/root of n)

which i make =-1.657 please tell me if this right because if its wrong my lookup table will not even help..

so now what i do with the t disribution table because i am confuse. i know degree of freedom is n-1 = 15. but i am confuse.