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After a circus came back from its country-wide tour, relatives of the animal tamer asked him questions about which animals travelled with the circus.

“Where there tigers?”

“Yes, in fact, there were seven times more tigers than non-tigers.”

“What about monkeys?”

“Yes, there were seven times less monkeys than non-monkeys.”

“Where there any lions?”

What is the answer he gave to this last question?

The graph of the function \(y=kx+b\) is shown on the diagram below. Compare \(|k|\) and \(|b|\).

Compare the numbers: \(A=2011\times 20122012\times 201320132013\) and \(B= 2013\times 20112011 \times 201220122012\).

Some inhabitants of the Island of Multi-coloured Frogs speak only the truth, and the rest always lie. Three islanders said:

Bree: There are no blue frogs on our island.

Kevin: Bree is a liar. She herself is a blue frog!

Clara: Of course, Bree is a liar. But she’s a red frog.

Are there any blue frogs on this island?

In the family of happy gnomes there is a father, a mother and a child. The names of the family members: Alex, Charlie and Jo. At the dinner table two gnomes made two statements.

Charlie said: “Alex and Jo are of different genders. Alex and Charlie are my parents”.

Alex said: “I am Jo’s father. I am the daughter of Charlie”.

Who is who? That is, what is the name of the father, the mother and the child, if it is known that each gnome lied once, and each told the truth once.

On the first day of school, in all three of the first year classes (1A, 1B, 1C), there were three lessons: Maths, French and Biology. Two classes cannot have the same lesson at the same time. 1B’s first lesson was Maths. The Biology teacher praised the students in 1B: “You have even better marks than 1A”. 1A’s second lesson was not French. Which class’s last lesson was Biology?

There are bacteria in a glass. After a second each bacterium divides in half to create two new bacteria. Then after another second these bacteria divide in half, and so on. After a minute the glass is full. After how much time will the glass be half full?

Anna, Vincent, Tom and Sarah each bought one apple for 10p from a fruit stand. How did they manage to do this, if they didn’t have any coins less than 20p and if the fruit stand didn’t have any change less than 50p?

A snail crawls along a wall, having started from the bottom of the wall. Each day the snail crawls upwards by 5 cm and each night it slides down the wall by 4 cm. When does it reach the top of the wall, if the height of the wall is 75 cm?