Page 275 - ICSE Math 8

THINK SMART

1. Your sock drawer is a mess. 12 black socks and 6 red socks are mixed together. What are the chances
that, without looking, you pick out a red sock?
2. There are 5 red and 5 black balls in a bag. To increase the probability of picking a red ball from the bag
one should:
(a) Add more red balls to the bag (b) Add few white balls to the bag
(c) Add more black balls to the bag (d) Add equal number of red and black balls

Maths Lab Activity

Objective: To perform a random experiment, note down the outcomes and find the probability
Step 1: Take a cubical die.
Step 2: Throw the die and note the number that appears on its upper face. Make a table in the given
format.

Number on the upper face Tally marks Frequency
1

2
3

4
5

6
Step 3: Repeat the above step 50 times and note the observations in the table.
Using the table, calculate the probability of getting each of the six numbers.
1. Probability of getting the number 1 = _______ 2. Probability of getting the number 2 = _____
3. Probability of getting the number 3 = _______ 4. Probability of getting the number 4 = _____

5. Probability of getting the number 5 = _______ 6. Probability of getting the number 6 = _____
The number with greatest probability is = _________
Conclusion: The die used is biased/unbiased. (Tick the correct answer.)

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