Hands-on math!

Washington State Math Olympiad
Hints and Solutions
2011 Grade 6 Number Sense

Problem

1) Joey finds 1/8 of a number and then finds 1/8 of that new number. How many times would he have to take successive halves of the original number to end up with the same final number?

2) Jamal bought a bag filled with a mix of his favorite candies. He counted them when he got home and found that he has 25% more lemon heads than jaw breakers and 30% more jelly beans than lemon heads. Fill in the blank: He has _____% more jelly beans than jaw breakers. Put your answer on the answer sheet.

3) What is the sum of all the two-digit numbers neither of whose digits are prime? For example, 42 is not one while 44 is because 4 is not prime.

4) A palindromic number is one which is the same read backwards and forwards. For example, 121 and 3443 are palindromic numbers. What is the next palindromic number after 79311397 and how much more is it?

5) Quint bought a car. He sold it to Rachael for 5/6 of the price he paid for it. Rachael sold it to Shawn for 1/5 less than she paid for it. Shawn sold it to Teddy for 3/4 of what he paid. Teddy paid $1200 for it. How much did Quint pay for it originally?