Answer:
He needs to work for 40 whole hours
Step-by-step explanation:
In this question, we are tasked with calculating the amount a Tv will cost Bob in terms of the number of hours he needs to work.
Let’s look at the total cost he has to pay.
a. $500
b. 8% tax = 8/100 * 500 = $40
c. He is paying 2 bills of $35 each making a total of 2 * $35 = $70
The total amount he is to pay is thus; 500 + 40 + 70 = $610
Let’s look at his income ;
a. Bonus $45
b. Birthday gift $85
The total amount of money he has asides his salary to offset the bill is 45 + 85 = $130
The balance to pay from his salary would be $610 - $130 = $480
The number of hours he has to work since he earns $12 per hour would be 480/12 = 40 hours of work
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:
Answer is D hope this helps :)
Step-by-step explanation:
A box has 6 sides so you multiply 16.7 and 6 and you’ll get 100.2
ANSWER IS 100.2in
