Suppose that IQ scores have bell-shaped distribution with a mean of 95 and a standard deviation of 16 . Describe where approximately 99.75 of IQ scores lie, Answer \[ \text { below } 79 \text { and above } 111 \] Obelow 47 and above 143 Obetween 47 and 143 Obelow 63 and above 127

Find the standard deviation of \( x \), given that \( \Sigma 4 x^{2}=14600, \Sigma 2 x=420 \) and \( n=20 \).

Which of the following is/are part of descriptive statistics? central tendency. variability. linear regression. correlation. all of the above.

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 \( \square \).

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 ?

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