Use addition, subtraction, multiplication, and/or division; Use each of the given numbers exactly once

Construct 42 out of 2, 3, 4, and 9

Construct 17 out of 1, 3, 3, and 6

Construct 52 out of 2, 5, 8, and 9

Solve for each of the letters A through E (they are each equal to an integer 1 through 5 exclusively), given the following:

B + A = 6

E + B = C

E + C + B = 8

Solutions for last time:

Modern Tic Tac Toe- (and all other rotations of this)

**4 9 2**

**3 5 7**

**8 1 6**

Bill Gatesβs puzzle- There are **31** windows left open. After going through the process a couple of times you should notice that the windows that stay open are the squares of every number (window 1, 4, 9, 16, 25β¦). Since there are 1000 windows in the room, the number of windows open will be the number whose square is closest to 1000 without going over (31 squared = 961).