Maths T Sem 3.docx

1 3  15  5 , nq= 60 x =45 > 5 4 4 45 n = 60 sufficiently large and npq = 4 45   X N 15 ,  approximately 4   11.5  15 15.5  15 X ) P ( 12  X  15)  P(11.5 < X < 15.5) = P( 45 45 4 4 X B( 60 , 0.25) , np = 60 x

= P ( -1.0435 < Z < 0.1491) = 0.4109

Hypothesis testing is a method of using sample data to test a statistical hypothesis about population parameter.

Null hypothesis is a statement about a population parameter that is assumed to be true.

Even if the mass of the packets of sweets is not known to be normally distributed, we can still apply Central Limit Theorem to approximate X by a normal distribution since the sample size is large. Hence, the calculations are still valid. Total Type 1 error is the error of rejecting a null hypothesis Ho, when it is in fact actually true./occurs when a true Ho is rejected. Critical region is the set of values of the test statistic for which the null hypothesis is rejected.