Question

A bag contains 33 red marbles, 6 white marbles, and 5 gray marbles. You randomly pick out a marble, record its color, and put it back in the bag. You repeat this process 220 times. How many white or gray marbles do you expect to get

Answer 1

Total 73 times we can expect white or gray marbles.

Step-by-step explanation:

Total number of marbles = 33

Number of white marbles  = 6

Number of gray marbles  = 5

Now, as we need to pick white or gray marbles, so favorable outcomes

=  6+ 5  = 11 marbles

Now, P(Picking out 1 white or gray marble)  = $\frac{\textrm{Total Favorable outcomes}}{\textrm{Total Outcomes}} = \frac{11}{33} = (\frac{1}{3})$

Here, the same experiment is repeated 220 times.

So, the Combined Prediction

= Probability at first attempt  x Number of repetitions

$= (\frac{1}{3} ) \times 220 = \frac{220}{3} = 73.33 \approx 73$

⇒The combined prediction after 220 attempts  = 73

Hence,  total 73 times we can expect white or gray marbles.