Number Operations and Calculation Methods - Short Problems


This is part of our collection of Short Problems.

You may also be interested in our longer problems on Number Operations and Calculation Methods.

Printable worksheets containing selections of these problems are available here:

Stage 3 ★ Sheet 1 Solutions            Stage 3 ★★ Sheet 1 Solutions
  Sheet 2 Solutions              Sheet 2 Solutions

Split Clock Face

KS 3 Short Challenge Level:

Challenge Level:1

Use 2 straight lines to split the clock face into 3 parts so that the sums of the numbers in each of the parts are equal.

50, 50, 50 and 50

KS 3 Short Challenge Level:

Challenge Level:1

Weekly Problem 16 - 2017
Aroon says his age is 50 years, 50 months, 50 weeks and 50 days old. What age will he be on his next birthday?

Fly Away

KS 3 Short Challenge Level:

Challenge Level:1

Weekly problem 50 - 2006
Can you work out the values of the digits in this addition sum?

2014 Even Numbers

KS 3 Short Challenge Level:

Challenge Level:1

What is the difference between the sum of the first 2014 odd numbers and the sum of the first 2014 even numbers?

Magic Error

KS 3 Short Challenge Level:

Challenge Level:1

Weekly Problem 12 - 2014
Two of the numbers in a 4x4 magic square have been swapped. Can you work out the sum of these numbers?

Missing Digits

KS 3 Short Challenge Level:

Challenge Level:1

Can you find the missing digits in this calculation?

Operational Decision

KS 3 Short Challenge Level:

Challenge Level:1

Weekly Problem 44 - 2014
What symbol should be inserted to make the equation true?

Measured Upside Down

KS 3 Short Challenge Level:

Challenge Level:1

Weekly Problem 49 - 2008
Baby can't stand up yet, so we measure her upside down. Can you use our measurements to work out how much Baby has grown in her first year?

Subtracting to 2008

KS 3 Short Challenge Level:

Challenge Level:1

Weekly Problem 2 - 2015
Can you work out the sum of the missing digits in this subtraction?

Hot Dogs

KS 3 Short Challenge Level:

Challenge Level:1

How many hot dogs did this hot dog lover eat on the first day of her binge?

In Sum-mary

KS 3 Short Challenge Level:

Challenge Level:1

Weekly Problem 14 - 2011
What does the sum of these three numbers tell us about their product?

Mathematical Ages

KS 3 Short Challenge Level:

Challenge Level:1

Weekly Problem 16 - 2009
Arrange these three famous mathematicians in order with the shortest-lived first.

Down and Along

KS 3 Short Challenge Level:

Challenge Level:1

Weekly Problem 50 - 2015
Can you work out the values of J, M and C in this sum?

Calculation 2000

KS 3 Short Challenge Level:

Challenge Level:1

Weekly Problem 49 - 2013
What is the value of 2000 + 1999 × 2000?

Identical Digit Multiplication

KS 3 Short Challenge Level:

Challenge Level:1

77 is multiplied by another two-digit number with identical digits. What is the product?

Alberta's Age

KS 3 Short Challenge Level:

Challenge Level:1

Weekly Problem 26 - 2011
Alberta won't reveal her age. Can you work it out from these clues?

Bus Route

KS 3 Short Challenge Level:

Challenge Level:1

Weekly Problem 17 - 2009
How far apart are the first and last bus stops in this bus route?

Filling Morecambe Bay

KS 3 Short Challenge Level:

Challenge Level:1

Weekly Problem 19 - 2016
"It would take 20 million years to fill Morecambe Bay from a bath tap". What does this imply is the approximate capacity of Morecambe Bay?

Sum Total

KS 3 Short Challenge Level:

Challenge Level:1

Weekly Problem 50 - 2013
Each letter in this sum represents a different digit. How many solutions are there?

Debasing the Coinage

KS 3 Short Challenge Level:

Challenge Level:1

Weekly Problem 18 - 2009
How much lighter will £5 worth of 5p's be with these new lighter coins?

354972

KS 3 Short Challenge Level:

Challenge Level:1

Weekly Problem 42 - 2016
What is the remainder when 354972 is divided by 7?

Reverse Subtraction

KS 3 Short Challenge Level:

Challenge Level:1

Weekly Problem 27 - 2006
What is the value of c in this subtraction?

Kangaroo Subtraction

KS 3 Short Challenge Level:

Challenge Level:2 Challenge Level:2

Weekly Problem 2 - 2010
Can you solve this 'KANGAROO' alphanumeric subtraction?

So Many Sums

KS 3 Short Challenge Level:

Challenge Level:2 Challenge Level:2

Weekly Problem 20 - 2007
In this addition each letter stands for a different digit, with S standing for 3. What is the value of YxO?

Palindromic Milometer

KS 3 Short Challenge Level:

Challenge Level:2 Challenge Level:2

At the beginning and end of Alan's journey, his milometer showed a palindromic number. Can you find his maximum possible average speed?

Digit Deletion

KS 3 Short Challenge Level:

Challenge Level:2 Challenge Level:2

Weekly Problem 14 - 2010
What is the largest number of digits that could be erased from this 1000-digit number, to get a surprising result?

Oldest and Youngest

KS 3 Short Challenge Level:

Challenge Level:2 Challenge Level:2

Weekly Problem 11 - 2017
Edith had 9 children at 15 month intervals. If the oldest is now six times as old as the youngest, how old is her youngest child?

Sum of 1s

KS 3 Short Challenge Level:

Challenge Level:2 Challenge Level:2

Can you find the last 5 digits of this sum?

Multiple Choice

KS 3 Short Challenge Level:

Challenge Level:2 Challenge Level:2

How many questions did Sarah answer correctly in this multiple choice exam?

Rolling Along the Trail

KS 3 Short Challenge Level:

Challenge Level:2 Challenge Level:2

Weekly Problem 32 - 2011
What could be the scores from five throws of this dice?

Multiplication Mistake

KS 3 Short Challenge Level:

Challenge Level:2 Challenge Level:2

Jane accidentally multiplied by 54 instead of 45, and her answer was 198 too big. What number did she multiply 54 by?

Adding Tricky Fractions

KS 3 Short Challenge Level:

Challenge Level:2 Challenge Level:2

What is the sum of these fractions?

Jam and Egg Sandwich

KS 3 Short Challenge Level:

Challenge Level:2 Challenge Level:2

Weekly Problem 33 - 2011
How many solutions can you find to this sum? Each of the different letters stands for a different number.

Bookshop

KS 3 Short Challenge Level:

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

Weekly Problem 3 - 2017
Books cost £3.40 and magazines cost £1.60. If Clara spends £23 on books and Magazines, how many of each does she buy?

Last Digit

KS 3 Short Challenge Level:

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

What is the last digit in this calculation involving powers?

Carry Over

KS 4 Short Challenge Level:

Challenge Level:1

Weekly Problem 24 - 2009
Each letter stands for a different digit, and S is non-zero. Which letter has the lowest value?