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In six baskets there are pears, plums and apples. The number of plums in each basket is equal to the total number of apples in the other baskets. The number of apples in each basket is equal to the total number of pears in the other baskets. Prove that the total number of fruits is divisible by 31.

Suppose that: \[\frac{x+y}{x-y}+\frac{x-y}{x+y} =3.\] Find the value of the following expression: \[\frac{x^2 +y^2}{x^2-y^2} + \frac{x^2 -y^2}{x^2+y^2}.\]

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?