The probability any one system works is 0.99
So the probability of any one system failing is 1-0.99 = 0.01, so basically a 1% chance of failure for any one system
Multiply out the value 0.01 with itself four times
0.01*0.01*0.01*0.01 = 0.000 000 01
I'm using spaces to make the number more readable
So the probability of all four systems failing is 0.00000001
Subtract this value from 1 to get
1 - 0.00000001 = 0.99999999
The answer is 0.99999999 which is what we'd expect. The probability of at least one of the systems working is very very close to 1 (aka 100%)
Step-by-step explanation:
the answer should be 18
I believe the answer is D
see the attached figure to better understand the problem
we know that
The equilateral triangle has three equal sides
so
in the equilateral triangle ABC
the height of the triangle is the segment BD
in the right triangle BCD
Applying the Pythagorean Theorem
solve for BD
substitute the values
therefore
<u>the answer is</u>
the height of the triangle is 
One way to solve it is writing two equations based on the info so
y = 5x + 10 for members
y = 6x for nonmembers
(the + 10 isn't included in the second equation because nonmembers won't pay a membership fee)
and to find their intersection point (where the values will be the same), you just set them equal to each other:
5x + 10 = 6x
subtract 5x
x = 10 classes
