#52 Bus change
I am about to get on the bus, but I don鈥檛 have the exact money for the 拢1 fare. The driver doesn鈥檛 give change so I hand over more than 拢1 and they keep the excess.
Once I have sat down, I realise that even though I didn鈥檛 hand over all my coins, the amount of money I had with me was the largest possible amount I could have had in change without being able to pay 拢1 (or any multiple of 拢1) exactly. How much did I have?
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#51 Birthday candles
Solution
If you start by blowing on one candle and work your way around the cake, blowing on each candle once, this will put out all the candles in seven puffs 鈥� and this is the fewest puffs you can do it in. The trick is to make sure each candle gets blown on an odd number of times.
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Quick quiz #44
1 NASA鈥檚 COBE satellite, launched in 1989, was the first to make detailed measurements of what?
2 With what recent breakthrough in genetics are the names Emmanuelle Charpentier and Jennifer Doudna associated?
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4 6, 28, 496, 8128 鈥� what sequence of numbers is this?
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Quick quiz #44
Answers
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5 Cracking