Given that mean=3750 hours and standard deviation is 300:
Then:
<span>a. The probability that a lamp will last for more than 4,000 hours?
P(x>4000)=1-P(x<4000)
but
P(x<4000)=P(z<Z)
where:
z=(x-</span>μ)/σ
z=(4000-3750)/300
z=0.833333
thus
P(x<4000)=P(z<0.8333)=0.7967
thus
P(x>4000)=1-0.7967=0.2033
<span>b.What is the probability that a lamp will last less than 3,000 hours?
P(x<3000)=P(z<Z)
Z=(3000-3750)/300
z=-2.5
thus
P(x<3000)=P(z<-2.5)=0.0062
c. </span><span>.What lifetime should the manufacturer advertise for these lamps in order that only 4% of the lamps will burn out before the advertised lifetime?
the life time will be found as follows:
let the value be x
the value of z corresponding to 0.04 is z=-2.65
thus
using the formula for z-score:
-2.65=(x-3750)/300
solving for x we get:
-750=x-3750
x=-750+3750
x=3000</span>
Answer:
<h2>36</h2>
Step-by-step explanation:
The median is the value that separates the higher half from the bottom half of the data sample (middle value).
We have
34, 36, 30, 37, 40, 30, 42
Write from the smallest to the largest number
30, 30, 34, 36, 37, 40, 42
Answer:
Step-by-step explanation:
Based on the question we are given the percentages of each of the types of candies in the bag except for brown. Since the sum of all the percentages equals 75% and brown is the remaining percent then we can calculate that brown is (100-75 = 25%) 25% of the bag. Now we can show the probabilities of getting a certain type of candy by placing the percentages over the total percentage (100%).
- Brown:
- Yellow or Blue:
....add the numerators
- Not Green:
.... since the sum of all the rest is 80%
- Stiped: .... there are 0 striped candies.
Assuming the <u><em>ratios/percentages</em></u> of the candies stay the same having an infinite amount of candy will not affect the probabilities. That being said in order to calculate consecutive probability of getting 3 of a certain type in a row we have to multiply the probabilities together. This is calculated by multiplying the numerators with numerators and denominators with denominators.
- 3 Browns:
- the 1st and 3rd are red while the middle is any. We multiply 15% * (total of all minus red which is 85%) * 15% like so.
- None are Yellow: multiply the percent of all minus yellow three times.
- At least 1 green: multiply the percent of green by 100% twice, since the other two can by any
Answer:
Please check the explanation.
Step-by-step explanation:
Given
a)
f(x) + g(x) = (2x - 1) + (2 - x)
= 2x -1 + 2 - x
= x + 1
b)
f(x) - g(x) = (2x - 1) - (2 - x)
= 2x - 1 - 2 + x
= 3x - 3
c)
g(-5) - f(-5)
Putting x = -5 in g(x) = 2 - x
g(x) = 2 - x
g(-5) = 2 - (-5) = 2+5 = 7
Putting x = -5 in f(x) = 2x - 1
f(x) = 2x - 1
f(-5) = 2(-5) - 1
= -10 - 1
= -11
Thus,
g(-5) - f(-5) = 7 - (-11) = 7+11 = 18
d)
f(x).g(x) = (2x - 1) (2 - x) = -2x² + 5x - 2
e)
f(g(x)) = f(2-x)
= 2(2-x)-1
= 4-2x-1
= 3-2x
