Data Management (MDM4U) · Counting Probability

Conditional Probability and Independence

30 tutor-authored questions for this Ontario curriculum expectation, ordered easiest to hardest, every one with a full worked solution. Work through all 30 with your weekly-lesson access code.

Start the 30 questions Curriculum: MDM4U-CP.6

Sample: the first question, solved

A bag has 5 red and 5 blue marbles. A red marble is drawn first (not replaced). Find the probability the second marble drawn is also red.

📘 Worked solution
4/9.

And one from the hard end

"60% of employees are engineers, 40% non-engineers. 70% of engineers have a master's; 30% of non-engineers do. Find the overall probability a random employee has a master's."

Solution shown after you try it in practice mode.

Work through all 30, easiest to hardest

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