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%)
        
             
        
        
        
Answer:
9.6
Step-by-step explanation:
q=4+0.8(7)
 
        
             
        
        
        
Answer:
Step-by-step explanation:
r = 7 cm
h = 15cm
pi = 3.14
Top and bottom (These questions drive you crazy when you don't know if there is both a top and bottom).
Area = 2* pi *r^2 = 2 * 3.14 * 7^2
Area = 2 * 3.14 * 49
Area =                                                        307.72  Don't round this.
Cylinder body
Cylinder body = Circumference * h = 2*pi * r * h
Cylinder body = 2* 3.14 * 7 * 15
Cylinder body =                                      <u> 659.4</u>
<u />
Total =                                                      967.12
Rounded        967.1     Answer
 
        
             
        
        
        
One tick behind one is 3/4, 1/8 is basically half of 1/4, so find 1/4 and find 1/8, 0 is sort of obvious but then not obvious. three ticks behind 3/4. 2 2/3, count UP from 1 1/4 to find 2 2/3. I really hope I helped! :)
        
             
        
        
        
Answer:
80 is less than or equal to 22+7x
8 DVDs
Step-by-step explanation:
I don't have the inequality signs sorry if you don't know its the symbol thats opening to the left with a line underneath 
80 is less than or equal to 22+7x 
subtract 22 
58 is less than or equal to 7x 
divide and flip the sign to the right 
x is greater than or equal to 8.29 
so he can buy 8 DVDs in total