Answer:
31.35%
Step-by-step explanation:
Initial reading:
In the box, there are:
- 6 Black pens
- 4 blue pens
- 7 red pens
Total number of pens in the box = 6 + 4 + 7
= 17
If we count pens as outcomes the total number of possible outcomes are 17.
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New reading:
Clarissa takes out a black pen from the box.
That reduces the number of black pens by 1 which increases the total number of pens by 1 as well.
So now:
- Number of black pens = 6 - 1 = 5
- Total number of pens = 17 - 1 = 16
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Probability:
[tex] \boxed{ \mathsf{probability = \frac{favorable \: outcomes}{total \: outcomes} }}[/tex]
If we want her to pick up a black pen, and she ends up picking one. So, we can say that the outcome is in our favor.
That makes it,
- the number of favorable outcomes = number of black pens
= 5
- and total outcomes = Total number of pens
= 16
[tex] \implies\mathsf{probability = \frac{5}{16} }[/tex]
For showing it as some percent we'll just multiply the fraction by 100
[tex] \implies \mathsf{ \frac{5}{16} \times 100 }[/tex]
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As a percent:
[tex] \implies \mathsf{ \underline{ 31.25 \: \% } }[/tex]
