A teacher instituted a new reading program at school. After 10 weeks in the​ program, it was found that the mean reading speed of a random sample of 19 second grade students was 90.7 wpm. What might you conclude based on this​ result? Select the correct choice below and fill in the answer boxes within your choice. ​(Type integers or decimals rounded to four decimal places as​ needed.)

Respuesta :

Complete question is;

The reading speed of second grade students in a large city is approximately normal, with a mean of 91 words per minute (wpm) and a standard deviation of 10 wrpm. A teacher instituted a new reading program at school. After 10 weeks in the​ program, it was found that the mean reading speed of a random sample of 19 second grade students was 90.7 wpm. What might you conclude based on this​ result? Select the correct choice below and fill in the answer boxes within your choice. ​(Type integers or decimals rounded to four decimal places as​ needed.)

Answer:

We would conclude that the new program doesn't seem to be more effective than the old program.

Step-by-step explanation:

We are given;

Population mean; μ = 91

Population standard deviation; σ = 10

Sample mean; x¯ = 90.7

Sample size; n = 19

Formula for z-score

z = (x¯ - μ)/(σ/√n)

z = (90.7 - 91)/(10/√19)

z = -0.131

From online p-value from z-score calculator attached, using z = -0.131; significance level = 0.05; one tailed, we have;

P-value = 0.4479

This is more than the significance level of 0.05. Thus, we would conclude that the new program doesn't seem to be more effective than the old program.