Page 269 - ICSE Math 7
P. 269
(g) The probability that it will rain tomorrow is 80%. The probability that it will not rain tomorrow
is _________.
1 2 3 4
(i) (ii) (iii) (iv)
5 5 5 5
(h) Two dice are thrown simultaneously. The number of outcomes having exactly one even
number is _________.
(i) 18 (ii) 27 (iii) 9 (iv) 12
2. Write True or False.
(a) Probability of an event which is sure to happen is 1.
(b) A random experiment is one whose outcomes are predictable.
(c) If a fair coin is tossed 4 times, the exact number of heads cannot be predicted accurately.
1
(d) The probability that the ceiling fan of the room is working is .
2
(e) Probabilities are ratios which can be expressed as fractions, decimals or percentages.
(f) Experimental probability comes closer and closer to theoretical probability if the number of
trials are large and are increasing.
(g) The experimental probability of getting a head can be 1 if the coin is tossed a few times only.
3. Fill in the blanks.
(a) Probability of an ____________ event is 0.
(b) Probability is measured on a scale of _______ to _______.
(c) A list of all possible outcomes of an experiment is called a _________________.
(d) If a coin is flipped to decide which of the two team starts the game, the probability of your
team starting the game is ________.
(e) In an experiment of throwing a fair die once, the sum of probabilities of all distinct outcomes
in the sample space is _______.
(f) Theoretical probabilities are based on the assumption that outcomes are _______________.
(g) An _______ is a subset of a sample space.
(h) A fair game is one in which the chances of winning and losing are ____________.
PRACTICE TIME
1. A spinner shown here is rotated once. The probabilities of various events 2
associated with the capital letters are shown on the probability line. 3
1 4
P Q R S T
0 .25 .5 .75 1 8 5
Identify the letter that corresponds to the following probabilities: 7 6
(a) P (odd number) (b) P (number less than 9) (c) P (negative number)
(d) P (multiple of 4) (e) P (at least 3)
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