Working systematically

There are 549 NRICH Mathematical resources connected to Working systematically
Egyptian Rope
problem

Egyptian Rope

Age
7 to 11
Challenge level
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The ancient Egyptians were said to make right-angled triangles using a rope with twelve equal sections divided by knots. What other triangles could you make if you had a rope like this?
How many Times?
problem

How many Times?

Age
7 to 11
Challenge level
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On a digital 24 hour clock, at certain times, all the digits are consecutive. How many times like this are there between midnight and 7 a.m.?
Watch the clock
problem

Watch the clock

Age
7 to 11
Challenge level
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During the third hour after midnight the hands on a clock point in the same direction (so one hand is over the top of the other). At what time, to the nearest second, does this happen?
Calendar Cubes
problem

Calendar Cubes

Age
7 to 11
Challenge level
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Make a pair of cubes that can be moved to show all the days of the month from the 1st to the 31st.
Team Scream
problem

Team Scream

Age
7 to 11
Challenge level
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Seven friends went to a fun fair with lots of scary rides. They decided to pair up for rides until each friend had ridden once with each of the others. What was the total number rides?
Seating Arrangements
problem

Seating Arrangements

Age
7 to 11
Challenge level
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Sitting around a table are three girls and three boys. Use the clues to work out were each person is sitting.
Pouring the Punch Drink
problem

Pouring the Punch Drink

Age
7 to 11
Challenge level
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There are 4 jugs which hold 9 litres, 7 litres, 4 litres and 2 litres. Find a way to pour 9 litres of drink from one jug to another until you are left with exactly 3 litres in three of the jugs.
Arranging the Tables
problem

Arranging the Tables

Age
7 to 11
Challenge level
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There are 44 people coming to a dinner party. There are 15 square tables that seat 4 people. Find a way to seat the 44 people using all 15 tables, with no empty places.
Two Dots
problem

Two Dots

Age
7 to 11
Challenge level
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Place eight dots on this diagram, so that there are only two dots on each straight line and only two dots on each circle.
Quadrilaterals
problem

Quadrilaterals

Age
7 to 11
Challenge level
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How many DIFFERENT quadrilaterals can be made by joining the dots on the 8-point circle?