Question

MathWizard likes to play a fun number trick on her friends. She tells them to think of a number. She then tells them to subtract their number from 2 and multiply the result by 5. To this product she tells them to add half the difference when 24 is subtracted from 12 times their original number.

(a) If I use the number 8 and follow MathWizard's steps, what number will I get?

(b) If you correctly apply MathWizard's steps to your favorite number, and then tell MathWizard your result, how can MathWizard quickly figure out what number you started with?

Answer 1

a) is -36
b) MathWizard can add 6, divide by five, and then find the difference between that number and 2