Answer:
Expected value = 190
Variance = 4000
Step-by-step explanation:
Let X be the number of the trials until the third success of the bad pump.
This implies that X is a negative binomial distribution
having θ = 20% = 0.2.
Now, if for example it will take X trials to use up the three pumps, then the total time is 10 min/trials + extra 10 minutes for the 3 bad pumps
This means the total time is written as;
T = 10X + (10 + 10 + 20)
T = 10X + 40
Mean which is also expected value of X is;
μ_x = 3/0.2 = 15
Variance of X is; σ²_x = 40
Thus;
Mean of T will be;
μ_T = 10μ_x + 40
μ_T = 10(15) + 40
μ_T = 190
Also, variance of T will be;
σ²_T = 10²•σ²_x
σ²_T = 100 × 40
σ²_T = 4000
Answer:
–3 – (–8) – (–2) = x
Step-by-step explanation:
–3 – (–8) – (–2) = x
Subtracting a negative is adding a positive
-3 +8+2 =x
Starting from left to right
5 +2 =x
7 =x
Two-fifths (

) of the square of the number j (j²)
j²
Answer:

Step-by-step explanation:

2^0 is 1 also m^0 is 1
2^2= 4, 2^3= 8 , 2^4= 16


The teacher would need 40 centimeters of tape to hang 10 student projects.
Step-by-step explanation:
Given,
Tape used to hang projects = 36 centimeters
Number of projects hanged = 9
We will find unit rate;
9 projects = 36 centimeters
1 project = \frac{36}{9}\ centimeters
9
36
centimeters
1 project = 4 centimeters
Therefore,
Tape needed to hang 10 projects = 4*10 = 40 centimeters
The teacher would need 40 centimeters of tape to hang 10 student projects.
Keywords: unit rate, multiplication