Question

Lex was thinking of a number. Alex divides by 2, then adds 5 to get an answer of 4. What was the original number?

Answer 1

9514 1404 393

Answer:

  -2

Step-by-step explanation:

Let x represent the original number. Then the transformation Alex does is ...

  x/2 +5 = 4

  x/2 = -1 . . . . subtract 5

  x = -2 . . . . . multiply by 2

The original number was -2.