Probability Stage 3 - Short Problems


This is part of our collection of Short Problems.

You may also be interested in our longer problems on Probability - Stage 3.

Tying the Rope

KS 3 Short Challenge Level:

Challenge Level:1

Sam is holding two lengths of rope, and Pat ties two of the loose ends at random. What ropes could they end up with, and with what probability?

Would You Like a Jelly Baby?

KS 3 Short Challenge Level:

Challenge Level:1

What is the smallest number of jelly babies Matt needs to remove from his pocket to guarentee he gets at least one of each flavour?

Collecting Marbles

KS 3 Short Challenge Level:

Challenge Level:1

A bag contains red, orange, green and blue marbles. How many need to be taken out to ensure that at least three are of the same colour?

Takeaway Time

KS 3 Short Challenge Level:

Challenge Level:2 Challenge Level:2

Pizza, Indian or Chinese takeaway. Each teenager from a class only likes two of these, but can you work which two?

Perfect Score

KS 3 Short Challenge Level:

Challenge Level:2 Challenge Level:2

Can you work out how many children answered all the questions correctly?

Monkey Puzzle

KS 3 Short Challenge Level:

Challenge Level:2 Challenge Level:2

Three monkeys each hung up their hats as they entered a cafe. They each took a hat at random when they left. What is the probability that they all took the correct hats?

Vegtown Elections

KS 3 Short Challenge Level:

Challenge Level:3 Challenge Level:3 Challenge Level:3

What percentage of people voted for the Broccoli party in the Vegtown election?

Counting Kangaroos

KS 3 Short Challenge Level:

Challenge Level:3 Challenge Level:3 Challenge Level:3

Can you work out how many kangaroos Rachel draws in one colour?

Counting Socks

KS 3 Short Challenge Level:

Challenge Level:3 Challenge Level:3 Challenge Level:3

Can you work out the smallest number of socks Rachel needs to take out of the box to be guaranteed a pair?