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:
1 1/3
Step-by-step explanation:
Find the common denominator of all three which is 6.
Then multiply each to make the common denominator 6
1/2*3 = 3/6
2/3*2 = 4/6
1/6*1 = 1/6
Then add all of them together
3/6+4/6+1/6 = 1 2/6
Simplified equals 1 1/3
A) The graph is misleading because it dosent give the number of students, it gives percentages.
b) A more appropriate way to display data would be a line graph because it shows the number of students favorite sports.
Substitute with y = 4 and z = -2
= 4^2*(-2)/4 + 10
= 16*(-2)/4 + 10
= -32/4 + 10
= -8 + 10
= 2
Hope This Helped! Good Luck!
Answer:
The name given to the shaded region would be the positive interval because all f(x) values in that region are positive.
