Question 4 (5 points)the points obtained by students of a class in a test are normally distributed with a mean of 60 points and a standarddeviation of 5 pointsabout what percent of students have scored between 55 and 65 points? a. 2.5b. 47.5c. 68d. 34

Option C

Step-by-step explanation:

Given

Mean= μ=60

and

Standard Deviation= σ=5

In order to calculate the percentage of students between 55 and 65, we have to calculate z-score for both

z-score for 55=(55-60)/5  

=(-5)/5

=-1

The area to the left of z-score -1 is 0.1587

z-score for 65=(65-60)/5  

=5/5

=1

The area to the left of z-score 1 is 0.8413

Area between z-scores of 55 and 65=0.8413-0.1587

=0.6826

Converting into percentage

=0.6826*100

=68.26%

Option C is the correct answer ..  

c. 68

Step-by-step explanation:

The empirical rule states that, if a population is approximately normal then 68% of the observations will fall within 1 standard deviation of the mean.

Going by this definition, 65 is one standard deviation to the right of the mean while 55 is one standard deviation to the left of the mean. Therefore, the percent of students who have scored between 55 and 65 points will be about 68%.

The question requires an approximation, About what percent, not exact computation. Thanks

answer: 2530

hope this

the correct answer option is (2x-3)(2x+3).

step-by-step explanation:

we are given the following expression and we are to factorize it:

we are to find such factors that when multiplied they give a result of 36 (9 x 4 = 36) and when added they give a result of 0.

the two such factors of 36 are negative six and postive six.

factorizing the given expression to get:

therefore, the correct factorization of is (2x-3)(2x+3).