This requires discussion among your friends during lunch time. You will come up with different numbers as you proceed with discussion.

 

One day early morning when the shop keeper opened his stationery store, an yound boy walked into buy a pen.

 

The pen cost was Rs.12. He gave Rs.20 note and since it was the first deal, the shopkeeper didnt have change. He went upto a pan shop and asked for change for Rs.20/-. He gave 20 numbers one rupee coin in exchange of the currency note. The shopkeeper kept Rs.12/- (12 coins) and returned Rs.8/- (8 coins) to the boy. the boy left with a pen worth Rs.12/- and Rs.8/-. A little later, pan shop owner came to shopkeeper and returned the Rs.20 note mentioning it was a fake note. The shop keeper had to give Rs.20 in exchange of the fake note.

 

Now the question is : How much total money the shop keeper lost in this transaction?

 

Have a nice discussion.

 

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