A bag contains $3$ red counters and $2$ blue counters. Two counters are selected. - Method A : R

Question

A bag contains $3$ red counters and $2$ blue counters. Two counters are selected. - Method A : Replace the first counter and mix before the second selection. - Method B : Do not replace the first counter. Calculate the probability of exactly one red using each method. Which method gives the greater probability of exactly one red, and by how much? If the aim changes to obtaining two reds, which method is better? Support your answer with calculations. Explain why the preferred method changes.

Accepted Answer

(a) A: $\frac{12}{25}$, B: $\frac{3}{5}$; (b) B by $\frac{3}{25}$; (c) A: $\frac{9}{25}$ versus $\frac{3}{10}$; (d) Removing a colour changes the next draw’s chances.

Probability

Probability

Solution:

Solution locked