Answer:
A) Pd = 13/28
B) Pd = 7/16
Step-by-step explanation:
Given;
Drama = 2
Comedy = 1
Science fiction = 5
Total = 8
a) The probability of selectingat least one drama movie Pd;
Pd = 1 - Pd'
Without replacement;
Probability of not selecting a drama movie Pd' is;
Pd' = 6/8 × 5/7 = 15/28
Pd = 1 - 15/28
Pd = 13/28
b) with replacement;
Probability of not selecting a drama movie Pd' is;
Pd' = 6/8 × 6/8 = 9/16
Pd = 1 - 9/16
Pd = 7/16
Answer:
0.74 to 6.06
Step-by-step explanation:
The groups are independnet,
SE(xh bar-xa bar)=sqrt [sh^2/nh+sa^2/na]=sqrt [10.1^2/80+10.3^2/80]=1.61
At df=157, the t critical is 1.65
90%c.i=(xh bar-xa bar)+-tcritical SE(xh bar-xa bar)
=(25.2-21.8)+-1.65*1.61
=0.74 to 6.06
The standard deviation is the square root of the variance
so if the variance is 3.6, the standard deviation is the sqrt 3.6...
sqrt 3.6 = 1.897 <= if u need it rounded, it is 1.9 grams