Step-by-step answer:
assuming the true-false test have equal probabilities (each 0.5), we can use the binomial probability to calculate the sum of probabilities of getting 10, 11 or 12 questions correctly out of 12.
p=probability of success = 0.5
N=number of questions
x = number of correct answers
then
P(x) = C(N,x)(p^x)((1-p)^(N-x))
where C(N,x) = N!/(x!(N-x)!) = number of combinations of taking x objects out of N.
P(10) = C(12,10)(0.5^10)((1-0.5)^2) = 33/2048 = 0.01611
P(11) = C(12,11)(0.5^11)((1-0.5)^1) = 3/1024 = 0.00293
P(12) = C(12,12)(0.5^12)((1-0.5)^0) = 1/4096 = 0.00024
for a total probability of 79/4096 = 0.01929
The first car is traveling at 65 miles per hour and the second car is traveling at 62 miles per hour.
Explanation:
390:x=372:(x-3)
372x=390(x-3)
372x=390x-1170
1170=390x-372x
1170/18=18x/18
x=65
x-3= 65-3=62
Answer:
20x +1
Step-by-step explanation:
do the exponite first. 4X4=16. then add on 4x, 16x+4x=20x, then add on 1
Answer:
0.3164 = 31.64% probability the team wins all its conference games
Step-by-step explanation:
For each conference game, there are only two possible outcomes. Either the team wins it, or they lose. The probability of winning a game is independent of any other game. This means that the binomial probability distribution is used to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

In which
is the number of different combinations of x objects from a set of n elements, given by the following formula.

And p is the probability of X happening.
A football team has a probability of .75 of winning when playing any of the other four teams in its conference.
The probability means that
, and four games means that 
If the games are independent, what is the probability the team wins all its conference games?
This is P(X = 4). So


0.3164 = 31.64% probability the team wins all its conference games
18×12.80=230.40 (class total)
11×12.80=140.80 (1st day)
230.40-140.80=89.60 (amount paid on 2nd day)
Other way
18-11=7
7×12.80=89.6