Working systematically

There are 549 NRICH Mathematical resources connected to Working systematically
Plate Spotting
problem

Plate Spotting

Age
7 to 11
Challenge level
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I was in my car when I noticed a line of four cars on the lane next to me with number plates starting and ending with J, K, L and M. What order were they in?
Palindromic Date
problem

Palindromic Date

Age
7 to 11
Challenge level
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What is the date in February 2002 where the 8 digits are palindromic if the date is written in the British way?
American Billions
problem

American Billions

Age
11 to 14
Challenge level
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Play the divisibility game to create numbers in which the first two digits make a number divisible by 2, the first three digits make a number divisible by 3...
Dodecamagic
problem

Dodecamagic

Age
7 to 11
Challenge level
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Here you see the front and back views of a dodecahedron. Each vertex has been numbered so that the numbers around each pentagonal face add up to 65. Can you find all the missing numbers?
Two and Two
problem

Two and Two

Age
7 to 16
Challenge level
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How many solutions can you find to this sum? Each of the different letters stands for a different number.
Nine Colours
problem

Nine Colours

Age
11 to 16
Challenge level
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Can you use small coloured cubes to make a 3 by 3 by 3 cube so that each face of the bigger cube contains one of each colour?
Family Tree
problem

Family Tree

Age
7 to 11
Challenge level
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Use the clues to find out who's who in the family, to fill in the family tree and to find out which of the family members are mathematicians and which are not.
Cayley
problem

Cayley

Age
11 to 14
Challenge level
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The letters in the following addition sum represent the digits 1 ... 9. If A=3 and D=2, what number is represented by "CAYLEY"?
Where can we visit?
problem

Where can we visit?

Age
11 to 14
Challenge level
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Charlie and Abi put a counter on 42. They wondered if they could visit all the other numbers on their 1-100 board, moving the counter using just these two operations: x2 and -5. What do you think?
What's Possible?
problem

What's Possible?

Age
14 to 16
Challenge level
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Many numbers can be expressed as the difference of two perfect squares. What do you notice about the numbers you CANNOT make?