In his bookstore toby places 21 books on shelves with 7 books on each shelf how many shelves does toby need

Three times the sum of a number and seven is negative thirty-six. what is the number?

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.

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