Math 1617 listings
NRICH: Pythagoras Perimeters
NRICH (University of Cambridge)

If you know the perimeter of a right angled triangle, what can you say about the area?

NRICH: Difference of Two Squares
NRICH (University of Cambridge)

What is special about the difference between squares of numbers adjacent to multiples of three?

NRICH: Hollow Squares
NRICH (University of Cambridge)

Which armies can be arranged in hollow square fighting formations?

NRICH: Harmonic Triangle
NRICH (University of Cambridge)

Can you see how to build a harmonic triangle? Can you work out the next two rows?

NRICH: Cuboid Perimeters
NRICH (University of Cambridge)

Can you find the volume of a cuboid, given its perimeters?

NRICH: Choir Boys
NRICH (University of Cambridge)

Can you work out how many members this choir has from these percentages?

NRICH: Brian's Number
NRICH (University of Cambridge)

Brian chooses an integer and operates on it. Work out the largest integer that he could have chosen.

NRICH: Puzzling Place Value
NRICH (University of Cambridge)

Can you explain what is going on in these puzzling number tricks?

NRICH: Square Number Surprises
NRICH (University of Cambridge)

There are unexpected discoveries to be made about square numbers…

NRICH: Find the Factor
NRICH (University of Cambridge)

Find a factor of 248−1.

NRICH: Length, Width and Area
NRICH (University of Cambridge)

The area of a rectangle is 225 square units. Find its width.

NRICH: Order the Products
NRICH (University of Cambridge)

Can you put these products in order of size?

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