GCE O/L Mathematics (Sri Lanka) · Mathematics

Sets, Statistics and Probability

43 practice questions, each with the answer and an explanation.

Practise Sets, Statistics and Probability now

Random questions from this topic, one at a time. You see the answer and the explanation straight after each one.

All 43 questions

Two fair dice are thrown. Find the probability that the sum is $8$ .
A box contains 7 red and 3 blue balls. Two balls are taken at random without replacement. Find the probability that they are of different colours.
In a group of students, $25$ study Sinhala, $21$ study Tamil and $3$ study both. How many study at least one of the two languages?
The mean of $2, 1, 8, 11, 3, 6, 11$ and $x$ is $10$ . Find $x$ .
Two fair dice are thrown. Find the probability that the sum is $4$ .
A box contains 4 red and 7 blue balls. Two balls are taken one after the other without putting the first back. Find the probability that both are red.
A can finish a job alone in $15$ days and B can finish it alone in $60$ days. A works alone for $5$ days and then B joins. For how many more days must they work together to finish the job?
How many subsets does a set with $5$ elements have?
The table shows the number of books read by $20$ students: $1$ book (2 students), $2$ books (5), $3$ books (4), $4$ books (9). Find the mean number of books.
Two fair coins are tossed. What is the probability of getting two heads?
A box contains 6 red and 5 blue balls. Two balls are taken one after the other without putting the first back. Find the probability that both are red.
A can finish a job alone in $12$ days and B can finish it alone in $20$ days. A works alone for $4$ days and then B joins. For how many more days must they work together to finish the job?
In a group of students, $20$ study Sinhala, $22$ study Tamil and $11$ study both. How many study at least one of the two languages?
Two fair dice are thrown. Find the probability that the sum is $7$ .
A box contains 8 red and 4 blue balls. Two balls are taken at random without replacement. Find the probability that they are of different colours.
The mean of $5, 13, 11, 19, 17$ and $x$ is $12$ . Find $x$ .
Two fair dice are thrown. Find the probability that the sum is $10$ .
How many subsets does a set with $6$ elements have?
Two fair dice are thrown. Find the probability that the sum is $6$ .
Class A has $10$ students with a mean mark of $59$ . Class B has $30$ students with a mean mark of $55$ . Find the mean mark of all the students together.
A box contains 3 red and 5 blue balls. Two balls are taken one after the other without putting the first back. Find the probability that both are red.
A can finish a job alone in $30$ days and B can finish it alone in $20$ days. A works alone for $5$ days and then B joins. For how many more days must they work together to finish the job?
In a group of students, $10$ study Sinhala, $15$ study Tamil and $7$ study both. How many study at least one of the two languages?
The mean of $13, 9, 5, 15, 15$ and $x$ is $10$ . Find $x$ .
A box contains 3 red and 8 blue balls. Two balls are taken one after the other without putting the first back. Find the probability that both are red.
A can finish a job alone in $20$ days and B can finish it alone in $30$ days. A works alone for $5$ days and then B joins. For how many more days must they work together to finish the job?
Of $38$ children, $22$ like cricket, $13$ like volleyball and $5$ like both. How many like neither?
The mean of $19, 6, 16, 13, 17, 4, 17$ and $x$ is $15$ . Find $x$ .
Class A has $10$ students with a mean mark of $66$ . Class B has $25$ students with a mean mark of $87$ . Find the mean mark of all the students together.
A box contains 5 red and 3 blue balls. Two balls are taken one after the other without putting the first back. Find the probability that both are red.
A can finish a job alone in $15$ days and B can finish it alone in $24$ days. A works alone for $2$ days and then B joins. For how many more days must they work together to finish the job?
Find the mean of $3, 19, 18, 8, 17$ .
A box contains 8 red and 6 blue balls. Two balls are taken at random without replacement. Find the probability that they are of different colours.
How many subsets does a set with $7$ elements have?
Find the mean of $24, 5, 8, 5, 19, 11, 12$ .
A bag has 6 red and 8 blue marbles. One marble is picked at random. Find the probability that it is blue.
A box contains 4 red and 8 blue balls. Two balls are taken at random without replacement. Find the probability that they are of different colours.
Find the mean of $19, 5, 8, 9, 9$ .
A box contains 5 red and 4 blue balls. Two balls are taken at random without replacement. Find the probability that they are of different colours.
In a group of students, $19$ study Sinhala, $20$ study Tamil and $11$ study both. How many study at least one of the two languages?
The table shows the number of books read by $17$ students: $1$ book (1 students), $2$ books (3), $3$ books (8), $4$ books (5). Find the mean number of books.
A bag has 4 red and 6 blue marbles. One marble is picked at random. Find the probability that it is blue.
Find the mean of $5, 13, 19, 8, 15$ .

Sets, Statistics and Probability

Practise Sets, Statistics and Probability now

All 43 questions

Keep practising

More GCE O/L Mathematics (Sri Lanka) topics

Ready for the full GCE O/L Mathematics (Sri Lanka) test?