Q.1.
Sam says that the sum of two prime numbers is always even. How could you prove if he is right or wrong?
Q.2.
Which of the following is a correct definition of 'proof'?
Q.3.
You can never work out the exact area of a circle; what is the proof?
Q.4.
When x is an integer, 2x - 1 will always be an odd number, regardless of the value of x; what is the proof?
Q.5.
To prove a result is the same as to ....... the result?
Q.6.
Simon says that if a number is not prime it will always have an even number of factors. Which of these statements proves that he is wrong?
Q.7.
If one of the angles in a triangle is 90° the other two angles must add up to 90°. What fact is used to prove the truth of this statement?
Q.8.
The word horse has 5 letters beginning with the letter H and so does the name Henry which proves Henry is a horse. Why is this statement false?
Q.9.
With the exception of the number 2, all prime numbers are odd numbers; what is the proof?
Q.10.
345,345,345,345 when doubled will be an even number; what is the proof?