Question

0.8998 24 d. What is the probability the number of fatal crashes will be between 1000 and 25 year? 26 27 28 e. What is the probability of more than 1750 fatal crashes a year due to drowsy drivers? 0.2525 31 f. What is the probability of no more than 1600 fatal crashes a year due to drowsy drivers? 32 0.5662 34 s. Given that the probability of there being more than 1700 crashes per year is 0.31, use this 35 information (not an Excel function) to find the probability of there being less than 1400 36 crashes per year due to drowsy drivers. 37 38 39 h. For a year to be in the upper 5% with respect to the number of fatal crashes, how many 40 fatal crashes would have to occur? 42 1. Within what range evenly distributed around the mean are the number of fatal crashes that occur in 75% 43 of the years? 44 lower upper: Name 01 02 03 04 Total Ready acer

st is 300 and mean is

Answer 1

CLT. We have, N= 1550, 6= 300 To solve all this problem we will use Lempus lint theroro 7. je. P[ Z44] = plx.de 2] P[2 LZ

Plx< 1000 ) = P(X-4 CX-550) = P(Z < 1000 - 1550 3oo -- Plz L -05) = P(Z < -1.8333) - 0.0 334 by p(x = 1000) = (x-4 x-1550 - P(Z < 1000 - 1550 300 < -1 8333) = P(Z P(xc 1000) = 0.0334 the Here, we have to less than get both find prob. 1000 and fo that some X is becaus we less of PC 10ook x < 200o = = PI 1000-da XoN a 2000- N 6 6 6 P 11000 - 1550< 300 < 2000- 1550 300 P(-1.83 3 3 2 2 = 1.5 - Prac15) - P(2<-1.83337

= 0 9331 - 0.0334 p (1000 < x < 2000)=0 8917 bet. Penie the will ber poob. that no 1000 82000 of 15 Fatal coashes 08997. PC X7 1750) = P(x - 4 x 1750-4 P ( Z7, 1750- 1550 30o P(Z < 1750-1550 - 1- PC ZL0.6666) = 1 -074749 = 0.25251. The poob. dear that due more than 1750 Forces to drowsy doxeos is coashes 0.25252. a P( x21600) = P(X-4 = 11 - = P(Z = 0.1666) 1600-) 550 300 - o 5666 0.56616 a I poob of dear no due more to than drowsy 1600 dover Fatcy coashes = 0.56616

one have, POX > 1700) = 0.3.1 Then p( x <1400)=P( x-N < 1400- iss = Pc z c .0.5) Iprx <1400) = 0.30854 Thus, poob. that there crashes per year is being less than 1900 = 0.3085 = 0.01