Shape products

These eleven shapes each stand for a different number. Can you use the multiplication sums to work out what they are?

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Problem

Shape Products printable worksheet

Shape Products printable worksheet - extra clues



The coloured shapes stand for eleven of the numbers from $0$ to $12$. Each shape is a different number.

Can you work out what they are from the multiplications below?  

  A

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Rectangle x Oval = Circle.

  B

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Square x Oval = Semicircle.

  C

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Rectangle x Rectangle = 8-pointed star.

  D

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Square x Square = Oval.

  E

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Triangle x Square = Circle.

  F

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Upside-down triangle x Semicircle = Upside-down triangle.

  G

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Square x 5-pointed star = Hexagon.

  H

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Diamond x Hexagon = Hexagon.



If you need some more clues, click below to reveal four more multiplications:

 

  I

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Square x Upside-down triangle = Upside-down triangle.

  J

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Rectangle x Square = Triangle.

  K

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Square x Square x Square = Semicircle.

  L

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Rectangle x Diamond = Rectangle.

 



Extension

Once you have worked out the value of each shape above, take a look at the two multiplications below:

 

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A 6 digit number multiplied by 3 equals another 6 digit number. The first six digit number has these digits in order: 1, circle, square, ring, tilted square, 6-pointed star. The second 6 digit number has these digits in order: circle, square, ring, tilted square, 6-pointed star, 1.

          

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A 6 digit number multiplied by 3 equals another 6 digit number. The first six digit number has these digits in order: 2, square, circle, tilted square, 6-pointed star, ring. The second 6 digit number has these digits in order: square, circle, tilted square, 6-pointed star, ring, 2.



Can you work out the value of the shapes in each product?

 

 

 

 

 

 

 

This activity originally featured in the hands-on Brain Buster Maths Boxes, developed by members of the NRICH Team and produced by BEAM. These resources are out of print but can still be found on Amazon.