A box in a certain supply room contains four 40w, five 60w, and six 75w light-bulbs. suppose that three bulbs are randomly selec
ted. a.what is the probability that exactly two of the selected bulbs are rated 75w?
b.what is the probability that all three of the selected bulbs have the same rating?
c.what is the probability that one bulb of each type is selected?
d.suppose, now, that bulbs are to be selected one by one until a 75w bulb is found. what is the probability that it is necessary to examine at least six bulbs?
Situation satisfies the criteria for the use of hypergeometric distribution. Since no replacement is made, binomial distribution is not applicable (probability does not remain constant).
A=number of target wattage bulbs B=number of non-targeted wattage bulbs a=number of target wattage bulbs selected b=number of non-targeted wattage bulbs selected
P(a,b)=C(A,a)*C(B,b)/C(A+B,a+b) where C(n,x)=combination of x items chosen from n=n!/(x!(n-x)!)
For all following problems, A+B=4+5+6=15 a+b=3 (selected)
(b) target wattage = each of the three Probability = sum of probabilities of choosing 3 40,60,75-watt bulbs P(3x40W)+P(3x60W)+P(3x75W) Case (A,B,a,b) 3x40W (4,11,3,0) 3x60W (5,10,3,0) 3x75W(6,9,3,0)
Scatter plots resembles line graphs in that they are plotted on the x and y axis. The are used because they show how much one variable is affected by another.
Scatter diagrams are important since in statistics they can show the extent of correlation, if any, between the values of observed quantities or a behavior.
A hummingbird flies at an average speed of 25-30 miles per hour and can do a fast dive at up to 60 miles per hour. A: Yes. A cheetah will run at about 70 miles per hour and a hummingbird flies at about 25-30 miles per hour.
It would be “Allen” since his percentage is far more grater then the rest, even Roneisha because even though her percentage is 1% greater, she has less pages, Ben has more pages but has 1% less.
Basically it’s like 2 bikers racing, 1 biker is faster but can’t go 5 miles, but the other is not that fast but can go 5+ miles.
