If we say that we have statistically significant results, we mean that the results are: very important. meaningless. likely to be due to chance differences between to be due to true differences between the groups.

Classifying subjects on the basis of gender is an example of what kind of measurement scale? nominal. ordinal. interval. discrete. continuous.

1. The blood pressure readings for executives are approximately normally distributed with a mean systolic blood pressure of 134 and a standard deviation of 20 . Given this information it can be concluded that: a about \( 68 \% \) of the executives have blood pressures between \( \square \) and \( \square \) b about \( 95 \% \) of the executives have blood pressures between \( \square \) and c about \( 99.7 \% \) of the executives have blood pressures between \( \square \) and d about \( 16 \% \) of the executives have blood pressures above \( \square \) e about \( 2.5 \% \) of the executives have blood pressures below \( \square \) f about \( 0.15 \% \) of the executives have blood pressures below \( \square \) g about \( 50 \% \) of the executives have blood pressures above \( \square \).

24. What is the \( y \)-intercept of the trend line equation, and what does it mean in the context of the situation?

Cite as características que um bom diagrama de dispersão deve ter para facilitar a interpretação dos dados.

The distribution of heights of 19 -year-old women is approximately normal, with a mean of 170 cm and a standard deviation of 5 cm . a What percentage of these women have heights: i between 155 and 185 cm ? ii greater than 180 cm ? iii between 160 and 175 cm ? b In a sample of 5000 of these women, approximately how many have heights greater than 175 cm ?