Question

Mathematics achievement test scores for 300 students had a mean and a variance equal to 550 and 3,600, respectively. If the distribution of test scores was mound-shaped, approximately how many of the scores would fall in the interval 490 to 610? (Round your answer to the nearest whole number.)

Answer 1

Answer:

number of scores between 490 and 610 is = 0.68 x 300 = 204

Step-by-step explanation:

The concept of Probability distribution is applied as it relates to the Z-scores.

Z = X - Mean /Standard deviation

The detailed steps and appropriate substitution is as shown in the attached file.