Probability

Experimental probabilities

Name: ______________________________Date: ______________Score: ______ / 20

1.
In 250 trials an outcome happened 15 times. What is the experimental probability, as a percentage?
%
2.
Why can you not calculate the probability of a drawing pin landing point up just by counting outcomes?
1. Athe two outcomes are not equally likely
2. Bthere are too many outcomes
3. Ca pin has more than two outcomes
3.
An experiment ran 200 trials. The relative frequency of success was 0.16. How many successes were there?
successes
4.
Running an experiment twice always gives exactly the same experimental probability.
True False
5.
Out of 100 trials an outcome happened 12 times. What is the relative frequency?
1. A3/25
2. B25/3
3. C3/22
6.
200 cars are counted and 120 of them are speeding. What is the experimental probability that the next car is speeding? Give it as a decimal.
7.
In 50 working days a driver stopped at the lights 45 times. What is the experimental probability of stopping, as a percentage?
%
8.
An experiment gives an experimental probability of 92% for an outcome. What is the experimental probability of it NOT happening?
%
9.
In 50 working days a driver stopped at the lights 42 times. What is the experimental probability of stopping, as a percentage?
%
10.
100 drawing pins are dropped. 36 land point up and 64 land point down. How many trials were there?
trials
11.
In 100 trials an outcome happened 30 times. What is the experimental probability, as a percentage?
%
12.
105 drawing pins are dropped. 51 land point up and 54 land point down. How many trials were there?
trials
13.
600 cars are counted and 180 of them are speeding. What is the experimental probability that the next car is speeding? Give it as a decimal.
14.
An experiment ran 80 trials. The relative frequency of success was 0.7. How many successes were there?
successes
15.
An experiment gives an experimental probability of 47% for an outcome. What is the experimental probability of it NOT happening?
%
16.
500 cars are counted and 140 of them are speeding. What is the experimental probability that the next car is speeding? Give it as a decimal.
17.
An experiment ran 240 trials. The relative frequency of success was 0.2. How many successes were there?
successes
18.
Out of 100 trials an outcome happened 10 times. What is the relative frequency?
1. A10
2. B1/9
3. C1/10
19.
In 50 working days a driver stopped at the lights 17 times. What is the experimental probability of stopping, as a percentage?
%
20.
An experiment gives an experimental probability of 17% for an outcome. What is the experimental probability of it NOT happening?
%

Answer key

Probability — Experimental probabilities

1.6 %
2.A. the two outcomes are not equally likely
3.32 successes
4.False
5.A. 3/25
6.0.6
7.90 %
8.8 %
9.84 %
10.100 trials
11.30 %
12.105 trials
13.0.3
14.56 successes
15.53 %
16.0.28
17.48 successes
18.C. 1/10
19.34 %
20.83 %