SECTION A: PROBABILITY
QUESTION 1
1.1. A bag contains a total of 10 marbles: 3 red marbles, 4 blue marbles, 2 green marbles, and 1
yellow marble.
1.1.1. If one marble is randomly drawn from the bag, what is the theoretical probability of
drawing:
1.1.1.1. Probability of drawing a red marble:
Number of red marbles = 3
Total marbles = 10
3
P(Red) = 10
1.1.1.2. Probability of drawing a blue marble:
Number of blue marbles = 4
Total marbles = 10
4 2
P(Blue) - 10 - 5
1.1.1.3. Probability of drawing a green marble:
Number of green marbles = 2
Total marbles = 10
2 1
P (Green) = 10 = 5
1.1.1.4. Probability of drawing a yellow marble:
Number of yellow marbles = 1
Total marbles = 10
1
P (Yellow) = 10
, So the probabilities are:
1.1.1.1 A red marble = 3/10
1.1.1.2 A blue marble = 2/5
1.1.1.3 A green marble = 1/5
1.1.1.4 A yellow marble = 1/10
1.1.2. Conduct an experiment where you draw one marble at a time from the bag and record the
colour, returning it each time. Repeat this 14 times. Use the table below to track your results:
Colour Drawn Tally Frequency
Red IIII 4
Blue 0
Green IIII 4
Yellow IIIII I 6
1.1.3. Based on the results you found in question 1.1.2, calculate the experimental probability for
each colour:
To calculate the experimental probability for each color, use the formula:
. Frequ . ncy of the ,e vent
P( vent) = --------
• To al number of trials
In this case, the total number of trials is 14 (since you drew a marble 14 times).
1.1.3.1. Probability of drawing a red marble:
4 2
P (R.ed) =- =-
14 7
1.1.3.2. Probability of drawing a blue marble:
' ' 0
P (Blue) = -. = 0
14
1.1.3.3. Probability of drawing a green marble:
4 2
P ( ! ;re,e n) == 14 == 7