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: This is rly confusing
Step-by-step explanation:
9514 1404 393
Answer:
6a^5b^7
Step-by-step explanation:
The applicable rule of exponents is ...
(a^b)(a^c) = a^(b+c)
__
It looks like you want to simplify ...
Answer:
The degree of the polynomial is 3
Step-by-step explanation:
Given:
To Find:
The degree of the polynomial= ?
Solution:
The degree of the polynomial is the value of the greatest exponent of any expression (except the constant ) in the polynomial. To find the degree all that you have to do is find the largest exponent in the polynomial
Here in the given polynomial
The terms are
The term has the largest exponent of 3
Note: The degree of the polynomial does not depend on coefficients of the terms
43.54 divided by 3.5= unit rate
12.44
