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World of Tan 18 - Soup

Age 7 to 11
Challenge Level

This activity follows on from World of Tan 17 - Weather.

Mah Ling and Chi Wing are about to take their lunch break. Some broth has been simmering on the stove in the kitchen. A warm, delicious smell wafts through the room. The others have gone back to work, having already eaten their lunch.

Mah Ling: They've left us a good amount for our lunch. Pass me your mug please - the broth is ready.

Chi Wing: You poured that well. It looks like we've got the exactly same amount of broth. How do you do it just by looking at it?

Mah Ling: I've had a lot of practice! You can pour out the next serving when we've finished these mugs.

Chi Wing: I can try, but I'd be worried about giving both of us fair servings.

Mah Ling: Eat up! We'll worry about that later.

A few minutes later...

Chi Wing: That was very warm and filling! Now, let me pour and see if I can get it equal for the pair of us.

Mah Ling: Stop, I have much more than you!

Chi Wing: It really isn't that easy to give two equal helpings. Can you help me try again?

Mah Ling: Okay, pour it all back into the pan. Now, choose a level in the mugs - up to the handle, say - and fill both to that level.

Chi Wing: And with what is left in the pan I can keep topping up each mug in turn. Oh, it's easy now... I've just never really had to think about it before, as I live on my own.

Mah Ling: That wasn't too difficult, but what about if we'd had mugs of two different shapes? How would you pour out fair shares then?

In the meantime, while thinking about what Chi Wing would do, you might like to complete the silhouettes of Chi Wing and Mah Ling eating their soup.

Extra activities:

  • Find a jug or bowl without any markings on the side, and fill it with water. Take two differently shaped cups or mugs. Can you put water from the jug into the two cups fairly, so that each cup has the same amount of water in it? How?
  • Have a look at this activity for more examples of sharing out food fairly.
The story continues in World of Tan 19 - A Circular Problem.