Daniela made her error on step 3 because it says:
"Find the ratio of the differences of the means compared to the mean absolute deviation.
She didn't find the difference between the today and last week means. She just put the mean as a whole.
This is a guess using logic, but my answer for this is that she concluded that she walked faster in the first 15 minutes. An increase in speed would increase the distance she walked in that amount of time
<span>the answer is M<13 for problems like this you can go to https://www.cymath.com/answer.php?q=solve%20M%20-%207%3C%206 to solve your answer</span>
The answer is a 8 days. the equation say's at the beginning of the day he read's 50 page's and later read's 14. this is everyday so. add 50+14+64. divide 400 by 64 and you get 7.8125, round that up and you get 8<span />
4/5 -3/7=
28/35 -15/35
=13/35