#247 Bargain birthday badges
Set by Alison Kiddle
Grandad has always been a bit of a cheapskate 鈥� and a little eccentric too. He鈥檚 sick and tired of buying birthday badges every year for his increasingly large family of grandchildren, all of whom have different birthdays.
鈥淐an鈥檛 we just use multiplication to save us buying quite so many badges?鈥� he suggested. 鈥淟ook, last year, Suzy turned 2 and Billy turned 7, so instead of wasting money on a badge for Joey鈥檚 14th, we could have just put the 2 and 7 together. We would all know that it means 2 脳 7.鈥�
The rest of the family weren鈥檛 enthusiastic, so Grandad sat down to work out just how much they would save in badges if they introduced the scheme (with the savings going straight into everyone鈥檚 piggy banks).
How few badges does Grandad need to buy if he wants to be able to make a set for any birthday from 1 to 21?
Solution next week
#246 Monoglots
Solution
The greatest possible number of monolingual delegates is 625. This requires 125 monolingual speakers of each language and 375 who speak all five languages.
Each language is spoken by 500 people. With five languages, that means there are 2500 language skills to be distributed among the 1000 delegates. If more than 625 delegates speak just one language, then the total count can鈥檛 add to 2500, even if the rest speak five languages each.
Quick quiz #227
set by Bethan Ackerley
1 The observation that, within genera of mammals and birds, those species in colder climates grow to larger sizes is known as what?
2 Which complex aromatic polymer forms much of the structure of wood, alongside cellulose?
3 Where would you find adipocere?
4 Who first confirmed James Clerk Maxwell's equations of electromagnetism in 1887?
5 When is Yuri's night, a celebration of milestones in space exploration, held each year?
Quick quiz #227
1 Bergmann's rule
2 Lignin
3 On dead bodies. Also known as grave wax, it is a soap-like substance created when body fat is broken down by anaerobic bacteria
4 Heinrich Hertz
5 12 April, the date when cosmonaut Yuri Gagarin became the first person to fly in space