Question 1199362
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Middle  20%  are those who are lower than upper  60%  and higher than lower 40%.


Use your calculator  TI-83 or  TI-84  with  function   invNorm.

Its format is   p = invNorm ( probability, mu, SD).


For details and instructions about this function and how to use it,  see web-site 

https://www.statology.org/invnorm-ti-84/   


The  z-scores are


        z_lower_40% = invNorm(0.4, 64, 2.3) = 63.4173.


        z_upper_60% = invNorm(0.6, 64, 2.3) =  64.5827.



<U>ANSWER</U>.  &nbsp;&nbsp;&nbsp;&nbsp;The middle &nbsp;20% &nbsp;of &nbsp;Martian heights lie between  &nbsp;63.42 &nbsp;and &nbsp;64.58 inches &nbsp;&nbsp;(after rounding).


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