Exploring and noticing

There are 412 NRICH Mathematical resources connected to Exploring and noticing
Number Squares
problem

Number squares

Age
5 to 11
Challenge level
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Start with four numbers at the corners of a square and put the total of two corners in the middle of that side. Keep going... Can you estimate what the size of the last four numbers will be?
Bean Bags for Bernard's Bag
problem

Bean bags for bernard's bag

Age
7 to 11
Challenge level
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How could you put eight beanbags in the hoops so that there are four in the blue hoop, five in the red and six in the yellow? Can you find all the ways of doing this?
Hallway Borders
problem

Hallway borders

Age
11 to 14
Challenge level
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What are the possible dimensions of a rectangular hallway if the number of tiles around the perimeter is exactly half the total number of tiles?
Only connect
problem

Only connect

Age
11 to 14
Challenge level
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The graph represents a salesman’s area of activity with the shops that the salesman must visit each day. What route around the shops has the minimum total distance?
Polite Numbers
problem

Polite numbers

Age
16 to 18
Challenge level
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A polite number can be written as the sum of two or more consecutive positive integers, for example 8+9+10=27 is a polite number. Can you find some more polite, and impolite, numbers?
Too Close to Call
problem

Too close to call

Age
11 to 14
Challenge level
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Weekly Problem 24 - 2012
Can you put these very close fractions into order?
Royal Arm Wrestling
problem

Royal arm wrestling

Age
11 to 14
Challenge level
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How many arm-wrestles will there be in the royal arm wrestling championship?
Road maker
problem

Road maker

Age
14 to 18
Challenge level
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Which of these roads will satisfy a Munchkin builder?
Almost Constant Digits
problem

Almost constant digits

Age
11 to 14
Challenge level
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How many 10-digit numbers containing only 1s, 2s and 3s can you write?
Magazines
problem

Magazines

Age
7 to 11
Challenge level
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Let's suppose that you are going to have a magazine which has 16 pages of A5 size. Can you find some different ways to make these pages? Investigate the pattern for each if you number the pages.