- Example of word problem solving 2
- Question:
- What number decreased by 12 equals 5 times the number?

- Solution:
- Let the number be x
- The number decreased by 12 expressed as x - 12
- 5 times the number expressed as 5x
- Given: the number decreased by 12 equals 5 times the number
- So we get the equation:
- x - 12 = 5x
- Move all veriables to the left side of the equation and move all numbers to the right side of the equation
- x - 5x = 12
- - 4x = 12
- divide -4 in both side of the equation
- x = -3
- so x = -3 is the solution

- Remark:
- when move one term to other side of the equation, the item will change sign.

This problem is translating english words into a mathematics expression and writting an equation. Let the number be x, then the number decreased by 12 can be written as x - 12. Five times the number can be written as 5x. The relationship is that the number decreased by 12 equals 5 times the number. So we get the equation x - 12 = 5x. Now make the equation into the standard form ax = b, then x = b/a. Check the value of x to see if it satisfy the equation.