Question

Rima is practicing math fluency. She has 100 math operation flashcards with 42 addition problem cards, 56 subtraction cards, and 2 multiplication cards. She will time herself to see how fast she can solve the problems on ten cards. She chooses her ten cards and they are all subtraction cards. Is choosing all subtraction cards likely? Explain by running a simulation.

Answer 1

notice how there are 100 total cards, and 56 subtraction cards. (so about half)

is it likely that **all ten cards** she chooses will be subtraction cards? (hint: since there are about half subtraction cards, it's similar to flipping a coin. is it likely that you'll get ten heads in a row if you flip ten coins?)

since it also wants you to run a simulation: you *could* make 100 cards with 56 subtraction cards, but that's a lot of work. you could, alternatively, make a virtual spinner and just make one section 0.56 and the other section 0.44 (adding up to 1, or 100%). put "number of spins" as 10 so it'll show you the results of ten spins. keep going over and over again, and see how likely it is that you'll land only on the 0.56 section.

http://www.shodor.org/interactivate/activities/AdjustableSpinner/