Toughest IIM's Riddle

Toughest  IIM'S Riddle   - 6 November

There is a shop that reads:
Buy 1 for $1.00
10 for $2.00
100 for $3.00
I needed 913 and still only paid $3.00. How could this be financially viable for the shop-keeper?


They are numbers for houses and it's $1 per digit

Soln By Shaukat Ahmad &

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