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A Jar of Teddies

Age 7 to 14
Challenge Level
In the image below, there are several different views of a jar that has been filled with teddies.
Can you estimate how many teddies there are in the jar?

Click below to see some different methods you might use to estimate it.

There are six different colours of teddy. I think there are around 8 to 10 of each colour. So there's between 48 and 60 teddies altogether.

There are about seven teddies visible on the top layer, and in the side view I counted around seven layers, so there must be about 50 teddies altogether.

I can see about fourteen teddies in the side view. There are about four layers of teddies going back, so there must be around $14 \times 4 = 56$  teddies altogether.

A teddy would fit in a 4cm by 4cm by 2cm space, which has a volume of 32 cubic centimetres. The jar is around 10 by 10 by 16 cm, which is 1600 cubic centimetres. 1600 divided by 32 is 50, so there are around 50 teddies.

Once you have made your estimate, click to reveal the exact number of teddies in the jar!

There are 55 teddies in the jar.

The bottom of the jar is 10cm square, and the jar is filled to a height of 16cm.
If we wanted to design a jar that would hold 100 teddies, what dimensions could it have?

Here is another teddy:

The larger teddy is 16cm tall, 19cm wide, and 12cm from front to back.

How many teddies like this do you think you could fit inside your classroom?

What other mathematical questions could you explore?