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2 years ago

Pippa has a box containing n pens.

Mathematics

1 answer:

Setler [38]2 years ago

6 0

The possible values of N from the given probability parameters is; N equals 15 or 21

<h3>How to Solve Algebra Problems?</h3>

We are told that;

Number of pens in the box = N

Let the number of red pens be x

Thus; number of black pens = x + 3

Thus;

x + x + 3 = N

x = (N - 3)/2

The probability that she will take a black pen followed by a red pen is;

P(she will take a black pen followed by a red pen) = (x + 3)/N * x/(N - 1)

Plugging in he relevant values and solving for N gives ;

Solving for N gives N equals 15 or 21

Read more about Algebra at; brainly.com/question/723406

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