### Contest 2017.10 Native American Day Math Contest

Sorry, the contest is over.  Come back in another week for Halloween Contest.

Operator Game is a fun and creative way to play with numbers. The goal of the Operator Game is to create an equation to reach the target number from 4 given numbers using a set of allowed operators.

Rules:

Operators allowed and points:

·       1 point: addition (+), subtraction (-).

·       2 points: multiplication (*), division (/).

·       3 points: exponent (2^3 or exp(2,3)), square root (sqrt(4))

Requirements: Each given number is used exactly once. No other numbers can be used. The same operator cannot be applied repeatedly if the result is the same or infinitely to get a converging number to avoid infinite points.

Goal: Find an expression with as many points as possible, using the given 4 numbers exactly once and the allowed operators to produce the target number.

Examples:

Numbers given are 2,3,4,5. Target number: 7

Possible solutions:

• Expression A: 5+((2+4)/3) = 7. Operators used: +, +, /. Total poins: 1,1,2 => 4
• Expression B: 3+5-(sqrt(4)/2) = 7. Operators used: +,-,sqrt, /. Total points: 1,1,3,2 => 7
• Expression C: 3+5-sqrt(sqrt(4)/2)) = 7. Operators used: +,-,sqrt,sqrt,/. Total points: 1,1,3,3,2 => 10
• Expression D: 3+5-sqrt(sqrt(sqrt(sqrt(4)/2)))) = 7. => Illegal expression since sqrt() was repeatedly applied to 1.
• Expression E: Exp(5 + sqrt(4),sqrt(3-2)) = 7. => 12 points.

Contest problems:

Problem A:

Numbers given: 1, 4, 6, 8.         Target number: 2.

Problem B:

Numbers given: 3, 10, 12, 13.         Target number: 10.

For youth under 18 years old, submit your answers for Problem A and B here.

Winner Board: To win a recognition on the winner board, please submit your expressions by midnight Sunday, Oct. 8, 2017.

Winner Prize:

Like it?  Join us in our upcoming "Logic, Patterns, and Problem Solving" Class

Any question? Email Contest@WonderlandMath.com.

### Tips on Operator Game

 Tips on the Operator Game: ·        Square Root: sqrt(4) = 2 because 4 = 2*2. Sqrt(9) = 3. Sqrt(100) = 10. ·        Exponent: 2^3 = 2 * 2 * 2. 5^2 = 5 * 5 = 25. Example 1: Numbers given are 2,3,4,5. Target number: 7 Expression A: 5+((2+4)/3) = 7. Operators used: +, +, /. Total poins: 1,1,2 => 4 Expression B: 3+5-(sqrt(4)/2) = 7. Operators used: +,-,sqrt, /. Total points: 1,1,3,2 => 7 Expression C: 3+5-sqrt(sqrt(4)/2)) = 7. Operators used: +,-,sqrt,sqrt,/. Total points: 1,1,3,3,2 => 10 Expression D: 3+5-sqrt(sqrt(sqrt(sqrt(4)/2)))) = 7. => Illegal expression since sqrt() was repeatedly applied to 1. Expression F: Exp(5 + sqrt(4),sqrt(3-2)) = 7. => 12 points. Other ways to make 7: 2^3 – sqrt((5-4)) = 7. => 8 points. 2*3+sqrt(5-4)=7. => 6 points 3*(2*sqrt(4))-5 => 8 poins.