2015 Grade 9 MTAP Math Challenge – Division Orals

Below are the 2015 Grade 9 MTAP Math Challenge Division Oral Competition questions with answers.

15-second question (2 points each)

1.) Determine all positive number x that satisfy 5x^2 = 10x.
Answer: x = 2

2.) What is the fourth power of \sqrt{2 + \sqrt{2}}?
Answer: 6 + 4 \sqrt{2}

3.) Simplify 4^{\frac{-k}{2}} + 8^ {- \frac{k-1}{3}}
Answer: \frac{3}{2}^k

4.) If a ♠ b = \sqrt{a^2+b^2}, what is the value of (3 ♠ 4) ♠ 12?
Answer: 13

5.) Suppose that x, y and z are positive integers such that xy = 6, xz = 10 and yz = 15. What is the value of xyz?
Answer: 30  Continue reading “2015 Grade 9 MTAP Math Challenge – Division Orals”