Individuals filing federal income tax returns prior to March 31 received an average refund of $1056. Consider the population of "last-minute" filers who mail their tax return during the last five days of the income tax period (typically April 10 to April 15). a. A researcher suggests that a reason individuals wait until the last five days is that on average these individuals receive lower refunds than do early filers. Develop appropriate hypotheses such that rejection of H0 will support the researcher’s contention.
b. For a sample of 400 individuals who filed a tax return between April 10 and 15, the sample mean refund was $910. Based on prior experience a population standard deviation of σσ = $1600 may be assumed. What is the p-value?
c. At αα = .05, what is your conclusion?
d. Repeat the preceding hypothesis test using the critical value approach.

Step-by-step explanation:

(A) Develop appropriate hypotheses such that the rejection of H0 will support the researcher's contention.

What is the researcher's contention?

The researcher's contention is that late filers receive lower refunds than early filers. Hence, the researcher's contention will be the alternative hypothesis; since the rejection of H0 will imply the acceptance of Ha (the alternative hypothesis).

To this regard, the appropriate hypotheses developed are:

H0: Late filers receive HIGHER refunds than early filers

H1: Late filers receive lower refunds than early filers

The rejection of H0 will lead to the acceptance of H1; which is in line with the researcher's contention/claim.

(x3 + 6x2 + 2x - 6) • (x - 1)

step-by-step explanation:

polynomial long division :

3.2     polynomial long division

dividing :   x4+5x3-4x2-8x+6

                              ("dividend")

by         :     x-1     ("divisor")

dividend     x4   +   5x3   -   4x2   -   8x   +   6

- divisor   * x3     x4   -   x3            

remainder         6x3   -   4x2   -   8x   +   6

- divisor   * 6x2         6x3   -   6x2        

remainder             2x2   -   8x   +   6

- divisor   * 2x1             2x2   -   2x    

remainder               -   6x   +   6

- divisor   * -6x0               -   6x   +   6

remainder                     0

quotient :   x3+6x2+2x-6   remainder:   0