Math Problem Statement

She pulls out 3 colored pencils. What are the probability that she pills out a green pink green? There are 12 colored pencils

Solution

To calculate the probability of pulling out pencils in the order green, pink, green, we will assume the pencils are pulled without replacement (as is common unless otherwise stated). Let’s calculate step by step:

Assumptions:

  • There are 12 pencils in total.
  • The number of green pencils = gg.
  • The number of pink pencils = pp.
  • We will denote the other pencils as oo, such that g+p+o=12g + p + o = 12.

Steps to Calculate Probability:

  1. Probability of pulling out the first green pencil: P(First green)=g12P(\text{First green}) = \frac{g}{12}

  2. Probability of pulling out a pink pencil after a green pencil: After removing 1 green pencil, there are 11 pencils left: P(Second pink | First green)=p11P(\text{Second pink | First green}) = \frac{p}{11}

  3. Probability of pulling out another green pencil after green and pink: After removing 1 green and 1 pink, there are 10 pencils left: P(Third green | Green, Pink)=g110P(\text{Third green | Green, Pink}) = \frac{g-1}{10}

Total Probability:

The total probability is the product of these probabilities: P(Green, Pink, Green)=g12p11g110P(\text{Green, Pink, Green}) = \frac{g}{12} \cdot \frac{p}{11} \cdot \frac{g-1}{10}

Final Expression:

P(Green, Pink, Green)=gp(g1)1320P(\text{Green, Pink, Green}) = \frac{g \cdot p \cdot (g-1)}{1320}

Next Step:

Please provide the specific numbers of green (gg) and pink (pp) pencils so I can give you the exact probability.


Do you want further details on this calculation or how it changes under different assumptions?

Related Questions:

  1. What is the probability if the pencils are replaced after being drawn?
  2. What if there are equal numbers of each color? How does this affect the result?
  3. How does the probability change if more than 3 colors are involved?
  4. Can we generalize this to calculate probabilities for pulling any sequence of colors?
  5. What is the probability if the order of pulling pencils doesn’t matter?

Tip:

When calculating probabilities involving multiple events, always clarify if items are replaced or not replaced, as it significantly affects the results!

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Math Problem Analysis

Mathematical Concepts

Probability
Combinatorics
Conditional Probability

Formulas

P(Green, Pink, Green) = (g/12) * (p/11) * ((g-1)/10)
P(Green, Pink, Green) = (g * p * (g-1)) / 1320

Theorems

Multiplication Rule of Probability

Suitable Grade Level

Grades 9-12