Answer: c)[50,60]
Step-by-step explanation:
The Empirical rule says that , About 68% of the population lies with the one standard deviation from the mean (For normally distribution).
We are given that , The heights of students in a class are normally distributed with mean 55 inches and standard deviation 5 inches.
Then by Empirical rule, about 68% of the heights of students lies between one standard deviation from mean.
i.e. about 68% of the heights of students lies between 
i.e. about 68% of the heights of students lies between 
Here, 
i.e. The required interval that contains the middle 68% of the heights. = [50,60]
Hence, the correct answer is c) (50,60)
To find the area of the shaded region, we must first find the percentage that is shaded.
We understand that 140 degrees out of 360 degrees are unshaded, thus there are 220 degrees shaded.
Thus the percentage is equal to 
Area = 
square yards
Hope that helps!
Answer: x=500
Step-by-step explanation:
Twenty more (+20) of a fifth of a number (.2x) is equal to 120. So, the equation would be .2x+20=120. To isolate x, subtract 20 from each side. So now we have .2x=100. To get rid of the .2 or 1/5, we have to multiply everything by the reciprocal of 1/5, or 5. So, 100(5)=.2x(5), or simplified, x=500. Hope this helps!
Answer1=1=4 quick mafffths
Step-by-step explanation:
you thought you were gonna cheat
54 is the answer, you could you use a calculator also
