Multiplying my age by 6 then subtracting 6 produces the same result as subtracting 7 from my age then multiplying by 7. How old am I?
On my broken calculator with keys + — ÷ x =, the only functional number is 7. How can I get 34 to appear in the readout?
A country mints four denominations of coins, in whole numbers of cents. It takes four of these coins to make 21¢, or 24¢, or 25¢, or 26¢. What are the denominations of the coins?
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