You have to calculate the expected value of pulling any number of good batteries.
There are 3 bad batteries (B) and seven good batteries (G)
If you pull two batteries the possible number of good batteries you can get are 0, 1 and 2.
GB, BG, GG, and BB
two chances for getting 1, one chance for getting two, and one chance for getting zero.
In order to calculate the expected value you have to first calculate the values of all the possibilities.
(GB = 7/10 x 3/10) (BG = 3/10 x 7/10) (GG = 7/10 x 7/10) (BB = 3/10 x 3/10)
Then take these answers and multiply them by the number of good batteries they each contain and add. (GB is 1 good battery, GG is two, etc.)
1(.21) + 1(.21) + 2(.49) + 0(.09)
The result is 1.4
The expected value of good batteries is 1.4
Answer:
90 mph
Step-by-step explanation:
if it can go 45 mph, in 2 hrs, it should go 90
45*2=90
0.63, 69%, 0.72 is the correct order
Step-by-step explanation:
8.8
Just add $5.35 and $3.45!
