Answer:
Probability = 0.8444
Step-by-step explanation:
To solve this problem, we need to obtain the z-value which corresponds to the probability that the mean of a sample of 84 computers would differ from the population mean by less than 1.39 months
Let x' denote the mean life of the computer.
Mean = 88 months
Variance = 81
Thus, standard deviation = √81 = 9
Thus, we obtain;
P(|x - μ| < 1.39) = P(-1.39 > x < 1.39)
For x' = - 1.39,
z = -1.39/(9/√84)
z = -1.39/0.982
z = -1.42
For x' = 1.39,
z = 1.39/(9/√84)
z = 1.39/0.982
z = 1.42
Thus, P(|x - μ| < 1.39) =
P(−1.42 < z < 1.42)
From the Z-distribution tables i attached, we obtain ;
0.92220 - 0.07780 = 0.8444
Answer:40Step-by-step explanation:
Answer:
x = - 16 , x = 24
Step-by-step explanation:
Given
f(x) = 0.5| x - 4 | - 3 and f(x) = 7, then equating gives
0.5|x - 4 | - 3 = 7 ( add 3 to both sides )
0.5| x - 4 | = 10 ( divide both sides by 0.5 )
| x - 4 | = 20
The expression inside the absolute value can be positive or negative, that is
x - 4 = 20 or - (x - 4) = 20
solving both
x - 4 = 20 ( add 4 to both sides )
x = 24
or
- (x - 4) = 20
- x + 4 = 20 ( subtract 4 from both sides )
- x = 16 ( multiply both sides by - 1 )
x = - 16
Answer:
46800
Step-by-step explanation:
10x15x24x13=46800