Averages

problem
Favourite

Wipeout

Age

11 to 16

Challenge level

Can you do a little mathematical detective work to figure out which number has been wiped out?
problem
Favourite

For Richer for Poorer

Age

14 to 16

Challenge level

Charlie has moved between countries and the average income of both has increased. How can this be so?
problem
Favourite

Stats Statements

Age

16 to 18

Challenge level

Are these statistical statements sometimes, always or never true? Or it is impossible to say?
problem

Kate's Date

Age

11 to 14

Challenge level

When Kate ate a giant date, the average weight of the dates decreased. What was the weight of the date that Kate ate?
problem

Balancing the Books

Age

11 to 14

Challenge level

How many visitors does a tourist attraction need next week in order to break even?
problem

Average Discovery

Age

14 to 16

Challenge level

Find the missing number if the mean, median and mode are all the same.
problem

Rugby and Ballet

Age

11 to 14

Challenge level

What is the average weight of five ballet dancers and ten rugby players?
problem

Partial Means

Age

14 to 16

Challenge level

From the mean of 64 numbers, and the mean of the first 36 of these numbers, can you work out the mean of the last 28 numbers?
problem

Better Spelling

Age

11 to 14

Challenge level

Weekly Problem 12 - 2010
Can Emily increase her average test score to more than $80$%? Find out how many more tests she must take to do so.
problem

Seven Dwarfs

Age

11 to 14

Challenge level

The Seven Dwarfs have seven different birthdays. How old can they be?