Life Changing Mindset

I am thinking of a positive number. If I square it, double the result, take half of that result, and then add?

I am thinking of a positive number. If I square it, double the result, take half of that result, and then add 12, I get 181. What is my number?

Public Comments

1. 13

2. 13

3. 2x^2)/2 +12=181
x^2+12=181
x^2=169
x=13

13

4. 2

5. x^2 * 2 / 2 + 12 = 181
x^2 + 12 = 181
x^2 = 169
x = 13

6. 13

7. 13

8. you can simplify the process by realizing that doubling and then halving is the same thing as not doing any multiplication or division at all.

positive number: x
squared: x^2
doubled, halved: x^2
add 12: x^2+12

set up the equation

x^2+12=181 subtract 12 from each side
x^2=169 apply the square root to each side
x=13

It is mathematically basic. The confusion comes from the wording and the excessive commas.

9. 7 is ALWAYS the answer....

10. Let the positive number be x.

Square it = x^2
Double the result = 2 * x^2 = 2x^2
Half of that result = 1/2 * 2x^2 = x^2
Add 12 = x^2 + 12
Result = 181 ---> x^2 + 12 = 181
x^2 = 181 - 12 = 169
x = sqrt (169) = 13.

Check:

Square 13 to get 169. Double 169 to get 169 * 2. Take half of that to get 169. Add 12 to 169 to get 181.

I hope that helps. :)

ILoveMaths07.

11. 13.
Solution:x^2*2/2+12=181
x^2+12=181
x^2=169
x=13.