logo for solving-math-problems.com
leftimage for solving-math-problems.com

order of processes - math puzzle











































math puzzle

There is a math question currently circulating on face book. What is the answer to this? 4 × 4 + 4 × 4 = 4 - 4 × 4. The answer I came up with is 20, based on my knowledge of order of processes, is this correct? Thank you in advance for your time and help.

Dave Abell

Comments for order of processes - math puzzle

Click here to add your own comments

Jan 11, 2013
math puzzle
by: Staff


Answer


There is no solution to this problem the way it is stated.

Regardless of where the parentheses are placed, the numerical value on the right hand side of the equation will never be equal to the value on the left hand side of the equation.

To be valid, the right hand side of the equation (4 - 4 × 4) must be equal to the left hand side of the equation (4 × 4 + 4 × 4). This is impossible with the numbers which are given.

The right hand side of the equation has only two possible values: 0 or -12

4 - 4 × 4

(4 - 4) × 4 = 0

4 - (4 × 4) = -12


For the entire equation to be valid, the left hand side of the equation must also equal 0 or -12 (one or the other).

The left hand side of the equation can never be equal to 0 because there are no negative numbers.

The left hand side of the equation can never be equal to -12 for the same reason: there are no negative numbers on the left side of the equal sign.

The left hand side of the equation will always yield a positive integer, no matter where the parentheses are placed.

For example:

4 × 4 + 4 × 4 =

(4 × 4) + (4 × 4) = 32

4 × (4 + 4) × 4 = 128

4 × (4 + 4 × 4) = 80
.
.
.
And so on


Final Answer:

4 × 4 + 4 × 4 ≠ 4 - 4 × 4






Thanks for writing.

Staff
www.solving-math-problems.com


Click here to add your own comments

Join in and write your own page! It's easy to do. How? Simply click here to return to Math Questions & Comments - 01.



Copyright © 2008-2015. All rights reserved. Solving-Math-Problems.com