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.
problem
Magic Error
Two of the numbers in a 4x4 magic square have been swapped. Can you work out the sum of these numbers?
problem
50, 50, 50 and 50
Aroon says his age is 50 years, 50 months, 50 weeks and 50 days. What age will he be on his next birthday?
problem
Split clock face
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.
problem
Identical digit multiplication
77 is multiplied by another two-digit number with identical digits. What is the product?
problem
Debasing the Coinage
How much lighter will £5 worth of 5p's be with these new lighter coins?
problem
Carry Over
Each letter stands for a different digit, and S is non-zero. Which letter has the lowest value?
problem
2014 even numbers
What is the difference between the sum of the first 2014 odd numbers and the sum of the first 2014 even numbers?
problem
Roses and Carnations
How many different bunches of flowers can this class buy for their teacher?
problem
Jam and Egg Sandwich
How many solutions can you find to this sum? Each of the different letters stands for a different number.
problem
Product and Sum
When Jim rolled some dice, the scores had the same product and sum. How many dice did Jim roll?
problem
Latin Multiplication
Can you choose one number from each row and column in this grid to form the largest possibe product?
problem
Filling Morecambe Bay
"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?
problem
Sum of Ten
The sum of ten distinct positive integers is 100. What is the largest possible value of one of the numbers?
problem
Anti-Magic Square
You may have met Magic Squares, now meet an Anti-Magic Square. Its properties are slightly different - can you still solve it?
problem
Palindromic milometer
At the beginning and end of Alan's journey, his milometer showed a palindromic number. Can you find his maximum possible average speed?
problem
So Many Sums
In this addition each letter stands for a different digit, with S standing for 3. What is the value of YxO?
problem
Currency Exchange
Dan and Ann have 9 and 8 coins respectively. What is the smallest number of coins they must swap so they end up with equal amounts of money.
problem
Digit Deletion
What is the largest number of digits that could be erased from this 1000-digit number, to get a surprising result?
problem
Squares and Cubes
How many positive two-digit numbers are there whose square and cube both end in the same digit?
problem
Sum One Special
Three different integers have a sum of 1 and a product of 36 - what are they?