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Probability, NAP-B4-NC28 SA

A coin is tossed 3 times. There are 8 possible outcomes.

What is the probability of getting 2 heads and 1 tail in any order?
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`3/8`

Show Worked Solution

`text(Strategy 1)`

`text{The table (array) below lists the possible outcomes:}`
 

  1st toss H H H H T T T T
  2nd toss H H T T H H T T
  3rd toss H T H T H T H T
       ✓  ✓    ✓      

`text(From table,)`

`Ptext{(2H, 1T)} = 3/8`
 

`text(Strategy 2)`

`text(This problem can also be efficiently solved using a)`

`text(probability tree.)`

Probability, NAP-B3-NC31 SA

Jon spins each pointer 50 times.

 

Each time he added the numbers that the pointers landed on.

His results are shown below.

\begin{array} {|c|c|c|c|c|c|}
\hline
\rule{0pt}{2.5ex}\textbf{Sum of numbers}\rule[-1ex]{0pt}{0pt} & 2 & 3 & 4 & 5 & 6 & 7 & 8 & 9 & 10 & 11 & 12 & \textbf{Total}\\
\hline
\rule{0pt}{2.5ex}\textbf{Number of spins}\rule[-1ex]{0pt}{0pt} & 1 & 2 & 3 & 6 & 8 & 9 & 7 & 5 & 4 & 4 & 1 & \textbf{50} \\
\hline
\end{array}

What percentage of the spins resulted in a sum of 9?

  %
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`text(10%)`

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`text(Percentage)` `= text(number of 9’s)/text(number of spins) xx 100`
  `=5/50 xx 100`
  `=10 text(%)`

Probability, NAP-E4-CA12

Peter has a bag of marbles. 75% of his marbles are blue.

Peter takes a green marble from his bag and loses it in a game.

If he takes another marble from the bag without looking, what are the chances it is blue?

 
 less than 75%
 
 equal to 75%
 
 greater than 75%
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`text(greater than 75%)`

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`text(There will be greater than 75% chance)`

`text(because there are the same amount of )`

`text(blue marbles to be chosen but 1 less)`

`text(in the bag.)`

Probability, NAP-G4-NC13

Brandi spins the arrow on two identical spinners.

The arrow on each spinner is equally likely to land on 1, 2 or 3.
 

If Brandi adds up the two results, which total is she least likely to get?

`2` `3` `4` `5`
 
 
 
 
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`2`

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`text{2 can only result from (1, 1).}`

`text(All other totals can have more than 1 combination producing them.)`

Probability, NAP-G4-CA02

Arun flips an unbiased coin 200 times.

Which result is most likely?

`20\ text(tails)` `98\ text(tails)` `108\ text(tails)` `196\ text(tails)`
 
 
 
 
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`98\ text(tails)`

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`text(The expected result is 100 tails.)`

`:.\ text(The most likely result is the one closest to 100 tails.)`

`=> 98\ text(tails)`