Step-by-step explanation:
are in the solution:
(3,1)
(-1,2)
(6,0)
(0,0)
are not
(-2,-1)
(0,-4)
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:
<u>The correct answer is A. 3,120.</u>
Step-by-step explanation:
Let's solve the expression for x = -5 and y = 25, this way:
(5|x| - y³)/x
Replacing x and y, we have:
(5 * 5 - 25³)/-5 (Absolute value of -5 is 5 in the numerator but we keep it without changes in the denominator)
(25 - 15,625)/-5
-15,600/-5
3,120
<u>The correct answer is A. 3,120.</u>
There is 2 cups in a pint
So the pints would equal 5 cups
Add the 1/2 cup.
Therefore she drank 5 1/2 cups
70% all you have to do is divide the 14 by 20
