Piggy bank

Shizuko discovered a box of small coins when she was tidying up at home. She took it to the bank and the final count realised an amazing 4510 yen!

​They were the smallest denomination, 1 yen!

How long did it take to amass so many, do you think? My guess is about 10 years.

Have you ever collected small things?

Coincidentally, I have an old sweet bottle in the office which I'm using to collect 1 yen coins. Students have been trying to work out how many there will be inside when its full based on the weight when full of sweets, 966 grams, and the fact that 1 yen weighs 1 gram.

I think we'll have to wait about another 2 years to find out!