Problems

Age
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Found: 3

In the context of Example 14.2 what is the answer if we have five numbers instead of four? (i.e., can we get four distinct prime numbers then?)

Four people discussed the answer to a task.

Harry said: “This is the number 9”.

Ben: “This is a prime number.”

Katie: “This is an even number.”

And Natasha said that this number is divisible by 15.

One boy and one girl answered correctly, and the other two made a mistake. What is the actual answer to the question?

Let \(p\) and \(q\) be two prime numbers such that \(q = p + 2\). Prove that \(p^q + q^p\) is divisible by \(p + q\).