Answer:
There is a 99.99998% probability that at least one valve opens.
Step-by-step explanation:
For each valve there are only two possible outcomes. Either it opens on demand, or it does not. This means that we use the binomial probability distribution to solve this problem.
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 combinatios of x objects from a set of n elements, given by the following formula.
And p is the probability of X happening.
In this problem we have that:
Calculate P(at least one valve opens).
This is 
Either no valves open, or at least one does. The sum of the probabilities of these events is decimal 1. So:
So
Finally
There is a 99.99998% probability that at least one valve opens.
The sum of the length of the two sides of the triangle must be greater than the length of the third side. None of the triangles is formed. Then option A is correct.
<h3>What is the triangle?</h3>
Triangle is a polygon that has three sides and three angles. The sum of the angle of the triangle is 180 degrees.
The sides of the triangle are 4.7 m, 1.6 m, and 2.9 m.
The condition will be
We know that the sum of the length of two sides of the triangle must be greater than the length of the third side.
Hence, none of the triangles is formed.
Thus, option A is correct.
More about the triangle link is given below.
brainly.com/question/25813512
Answer:
3/10
Step-by-step explanation:
Multiples of 3: 3,6,9,12,15,18
There are 6 in the numbers 1-20
P(multiple of 3) = number of "multiples of 3" / total
= 6/20
=3/10
