Answer:
C
Step-by-step explanation:
width = x
length = 2x+8
area = l x w
x<span>(2x+8)</span>=120
<span><span>2<span>x^2</span>+8x−120=0 </span>
</span>
<span><span><span>x^2</span>+4−60=0 </span></span>
<span><span><span>(x+10)</span><span>(x−6)</span>=0</span>
</span>
<span><span>x=−10 and x=6 </span></span>
<span><span> width has to be a positive number</span></span>
Width = <span>6
</span> inches.
Answer:
Radius= 2r
Step-by-step explanation:
Surface area of hemisphere
=2 x 22/7 x (2r)^2
=44/7 x 4 r^2
=174/7 r^2
=25.14 r^2
Question options :
a. They should be between 64 and 76 inches tall.
b. They should be close to the height that is 95% of the mean. That is, 66.5 inches, plus or minus 2 standard deviations.
c. They should be at or below the 95th percentile, which is 74.92 inches.
d. None of the above.
Answer: a. They should be between 64 and 76 inches tall.
Step-by-step explanation:
Given the following :
Assume men's height follow a normal curve ; and :
Mean height = 70 inches
Standard deviation= 3 inches
According to the empirical rule ;
Assuming a normal distribution with x being random variables ;
About 68% of x-values lie between -1 to 1 standard deviation of the mean. With about 95% of the x values lying between - 2 and +2 standard deviation of mean. With 99.7% falling between - 3 to 3 standard deviations from the mean.
Using the empirical rule :
95% will fall between + or - 2 standard deviation of the mean.
Lower limit = - 2(3) = - 6
Upper limit = 2(3) = 6
(-6+mean) and (+6+ mean)
(-6 + 70) and (6+70)
64 and 76
