Answer:
19.51% probability that none of them voted in the last election
Step-by-step explanation:
For each American, there are only two possible outcomes. Either they voted in the previous national election, or they did not. The probability of an American voting in the previous election is independent of other Americans. So we use the binomial probability distribution 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.
42% of Americans voted in the previous national election.
This means that 
Three Americans are randomly selected
This means that 
What is the probability that none of them voted in the last election
This is P(X = 0).
19.51% probability that none of them voted in the last election
Step-by-step explanation:
If x = the amount of 12% and y = the amount of 20%, then x + y = 80
Since we need 80 grams of 15%, 80(.15) = 12.
We are given that .12x + .20y = 12.
We can solve the first equation for x or y. Let's do x.
x = 80 - y
.12(80 - y) + .20y = 12
9.6 - .12y + .20y = 12
.08y = 2.4
y = 30
x = 80 - 30 = 50
Answer:
28 m
Step-by-step explanation:
The longer side can be found using the Law of Cosines. The semi-diagonals are of length 12 and 20 m, and the angle between them facing the long side is 180° -60° = 120°.
c^2 = a^2 +b^2 -2ab·cos(C)
c^2 = 12^2 +20^2 -2·12·20·cos(120°) = 144 +400 +240 = 784
c = √784 = 28
The longer side is 28 meters.
You have to find the discriminat b^2 -4ac
If it is > 0, the function has two real solutions
if it is = 0, the function has one real solution
if it is <0, the function has no real solution
6^2 - 4(7)(3) = 36 - 84 = - 48
Answer c. no solution
Answer:
24/100
Step-by-step explanation: