1turn = 360 half a turn is 180
360+180=540
Answer:
The length and width of the rectangle are 20 feet and 31.25 feet, respectively.
Step-by-step explanation:
Let the scale be
and the dimensions of the rectangle being 4 inches and 5 inches, respectively. The scale (
), measured in inches per feet, is equivalent to the following rational number:

We can convert each length by dividing it by scale factor. That is:
Length


Width


The length and width of the rectangle are 20 feet and 31.25 feet, respectively.
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>
$45,600
12 (200 + 75s)
12 ((200 + 75 (48))
12 ( 200 + 3600)
12 (3800)
45600