Question

The answers are in red. Please break it all down for me. I would really appreciate it!

The average income tax refund for the 2009 tax year was $3007. Assume the refund per person follows the normal probability distribution with a standard deviation of $965. Complete parts a through d below. a. What is the probability that a randomly selected tax return refund will be more than $2000? 0.8508 (Round to four decimal places as needed.) b. What is the probability that a randomly selected tax return refund will be between $1600 and $2900? 0.3834 (Round to four decimal places as needed.) c. What is the probability that a randomly selected tax return refund will be between $3400 and $4500? 0.2810 (Round to four decimal places as needed.) d. What refund amount represents the 35th percentile of tax returns? $ 2635 (Round to the nearest dollar as needed.)

Answer 1

Saution XNN(UI2) 6= 965 PCX2000)-p(x<2000.). E-PCX-U 6 2006-3007 11 ges PCZ-10435). -A483 -o1483 O-8516 Pix2000) 0-851)6 pc1so0 x250o) =P600-3007 365 2go0-300t X-4 965 pl-14580 2-0-11 03). PCZ-01l08)- pcz <-lg580) 0-4 558-0.0724 0.3839 1 PC1600KX290o) 6.28 39

PC 3400X 4500) = Pl34r0e 2007 4500-3007 965 965 PC 0-4072 Cz<1541) P(z<1s41)-pczco.te72) O.9390-06S80 PC3toox4s00 0.2810 pCxx)= 0.35 -300t 035 g65 p(z-3007 965 O-35 X-3007 965 by Using Exce) M-03853 2635 je x= $2635