6th Grade Math Challenge

6 piles of marbles are arranged in a triangle pattern. Each side of the triangle has total of 9 marbles. Add 1 more marble to one of the piles, so that the total number of marbles on each side remains 9. You are allowed to move the marbles but not take any out.

Fill each square with a number to make the subtraction result correct.

Find the sequence and fill in the blanks

(2, 3), (4, 6), (6, 9), (8, 12) ....

The 8^{th} group is (__, __)

5th Grade Math Challenge

Color all the shapes so that no adjacent shapes have the same color. What is the minimum number of colors you need?

Find the sequence and fill in the blanks

a) 45, 30, 18, 9, __, 0

b) 2, 5, 11, 23, 47, __, __

The following is an square array of 16 dots with 4 rows and 4 columns. The red dots are on the outside of the array. If you use 144 dots to form a square array,

(a) how many rows and columns are there?

(b) how many dots are on the outside of the array?

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