Aresearcher measures mean health scores of children at a local school and compares these scores to the mean health score known in the general population. assuming that the population variance is unknown, what type of t test is appropriate for this study? a. one-sample t test b. two-independent sample t test c. there is not enough information to answer this question.

b. two-independent sample t test

Step-by-step explanation:

the question stated that the variance is unknown, and standard deviation is paramount for a t test calculation.

the t-value is determined from the relationship

t = (x−µ) s

where x is the mean value of a sample, µ is the mean value of the population from which the sample is drawn,

s is the standard deviation of the sample and

N is the number of independent observations in the sample.

therefore, for independent sample t test, the variance can be calculated from the values of the two mean given with the sample size.

, and

for

step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

note the following:

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

, and for

answer:   (s+1)(s+4)

step-by-step explanation:

factor s2+5s+4

s2+5s+4

=(s+1)(s+4)