Does somebody understand this ?

Logan wants to know how many skateboards have defective parts. he inspects 20,000 skateboards and keeps track of the number of defects per board. use his probability distribution table to find the expected value for defects on a skateboard.

In order to be invited to tutoring or extension activities a students performance 20 point higher or lower than average for the

Zach spent 2/3 hour reading on friday a 11/3 hlurs reading on saturday. how much more time did he read on saturday tha on friday