Three textbooks have a mean weight of 18.1 (3) pounds, with a standard deviation of 1.15 pounds. A cardboard shipping box has a mean weight of 0.52 pounds with a standard deviation of 0.14 pounds. What are the mean and standard deviation of the weight of a shipping box packed with three textbooks? Mean \( =18.62 \quad \) S.D. \( =[?] \) Round to \( ] \)

2.50. Uz jautājumu "Cik minūtes nepieciešamas, lai skolēns no mājām atnāktu uz skolu?" 60 pirmo klašu skolēnu vecāki atbildēja šādi: \( 5 ; 4 ; 28 ; 28 ; 11 ; 17 ; 17 ; 10 ; 19 ; 27 ; 22 ; 9 ; 26 ; 5 ; 19 ; 21 ; 21 ; 21 ; 7 ; 2 ; 8 ; 14 ; 5 ; 20 ; 13 ; 24 ; 14 ; 15 \); \( 3 ; 29 ; 13 ; 13 ; 22 ; 17 ; 2 ; 26 ; 30 ; 14 ; 8 ; 1 ; 20 ; 15 ; 16 ; 21 ; 20 ; 18 ; 25 ; 8 ; 12 ; 24 ; 9 ; 27 ; 8 ; 9 ; 13 ; 2 ; \) \( 8 ; 19 ; 16 ; 23 \). a) Sakārto datus tabulā, grupējot tos no 1 līdz \( 5 ; \) no 6 līdz 10; no 11 līdz 15; no 16 līdz 20; 21 un vairāk minūtes! b) Nosaki datu modu! c) Aprēkini katras datu grupas relatīvo biežumu! d) Izmantojot tabulas datus, uzzīmē relatīvo biežumu stabinu diagrammu!

Why is data collection appropriate for this two-sample proportion procedure? Because the order of applying the two treatments to each doctor was randomized in this matched pairs design. Because two separate simple random samples were taken-one from each population. Because the doctors were randomly allocated to the two treatments (aspirin and placebo).

How do you identify the relationship between two variables in a scatter plot?

You run a regression analysis on a bivariate set of data ( \( n=88 \) ), You obtain the regression equation \[ y=0.231 x-8.928 \] with a correlation confficient of \( r=0.38 \) (which is significant at \( \alpha=0.01 \) ), You want to predict what value (on average) for the explanatory variable will give you a value of 90 on the response variable. What is the predicted explanatory value? \( x=\square \)

Knowing that \( 99.7 \% \) of all \( z \)-scores are between -3 and +3 , what is the \( P \)-value for \( z=-5.14 \) ? 0.000 0.0514 0.2981