Page 271 - ICSE Math 7

THINK SMART

1. In the adjacent spinner colour the sectors such that:
(a) probability of red is 0.3. (b) probability of blue is 0.4.

(c) probability of green is 0.1. (d) probability of yellow is 0.2.

2. Write each letter in the word ‘ASSASSINATION’ on a separate slip of paper and put them in a
bag. Without looking, take out one chit at random. Find each of the following.
(a) P (selecting A) (b) P (selecting S) (c) P (selecting a vowel)

(d) P (selecting T) (e) P (choosing any letter) (f) P (choosing Z)
3. A coin is tossed and it lands anywhere within the region with equal likelihood. Find the probability

that the coin will land on the shaded region. (These figures are not drown to scale.)

(a) 3 m (b) (c)

1 m

Maths Lab Activity

Conduct the following experiment and fill the given table:
A paper glass is tossed in the air. The different ways it can land are:

bottom top side
Toss the glass 30 times and keep the record of the outcomes.

Event Tally bars Frequency
Bottom
Top
Side

(a) From the data so collected find the experimental probability of each outcome.
(b) What is the theoretical or classical probability of these outcomes?

(c) On increasing the number of trials, the experimental probabilities of the events discussed
above comes closer and closer to the theoretical or classical probabilities. Do you agree?
Give reasons.

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