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.
Answer:
x= -4
Step-by-step explanation:
Simplifying
5x + -4 = 7x + 4
Solving
-4 + 5x = 4 + 7x
Move all terms containing x to the left, all other terms to the right.
Add '-7x' to each side of the equation.
-4 + 5x + -7x = 4 + 7x + -7x
Combine like terms: 5x + -7x = -2x
-4 + -2x = 4 + 7x + -7x
Combine like terms: 7x + -7x = 0
-4 + -2x = 4 + 0
-4 + -2x = 4
Add '4' to each side of the equation.
-4 + 4 + -2x = 4 + 4
Combine like terms: -4 + 4 = 0
0 + -2x = 4 + 4
-2x = 4 + 4
Combine like terms: 4 + 4 = 8
-2x = 8
Divide each side by '-2'.
x = -4
Simplifying
x = -4
Answer:
0.007
Step-by-step explanation:
A negative notation starts with 0's from the left.
count 3 places before the 7, that is where my point is.
I am pretty sure of my explanation but the answer is correct.
Answer:
16 pies were neither apple nor peach.
Step-by-step explanation:
8/10, or 4/5 of the 80 apple pies were either apple or peach, which 4/5 of 80 is 64. The remaining pies will be neither apple nor peach. 80 - 64 = 16.
Answer:
c>16
Step-by-step explanation:
c-12>4
c> 4+12
c> 16