We know that
[scale factor ]=[real]/[drawing]
[real]=[drawing]*[scale factor ]
step 1
find the real values
if the base of Riley's drawing is 10 centimeters
[real]=[drawing]*[scale factor ]--------> 10*3-------> 30 cm
the base of the triangular clock face is 30 cm
the height of Riley's drawing is 15 centimeters
[real]=[drawing]*[scale factor ]--------> 15*3-------> 45 cm
the height of the triangular clock face is 30 cm
the area of the triangular clock face is-----> 45*30/2-------> 675 cm²
the answer is the option C. 675 square centimeters
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:
3, 4 , 5 , 6 is your answer.
I HOPE IT WILL HELP YOU.
Thank you.
<u>TEDDYLOVER</u><u>.</u><u>.</u><u>.</u><u>.</u>
The answer is 11 becauze the pattern works like this - 18÷2=9 20÷2=10 22÷2=11 Basically the X axis being divided by 2 which equals the Y axis (eg: X÷2=Y
I hope this helps... try the app called photo math
