Question

Procedure: Pick a number. Add 5 to the number and multiply the sum by 3. Subtract 7 and then decrease this difference by the triple of the original number.

Answer 1

(3n +8) -3n = 8

Explanation:

You have the difference (3n+15) -7, and you want its value when it is decreased by the triple of the original number (n).

Triple the number

The phrase "triple the original number" will be translated to 3n. This is the value you want to subtract.

(3n +15) -7 = 3n +8 . . . . . "the difference"

(3n +8) -3n = 8 . . . . . . . . "decreased by triple the original number"

This simplifies to 8, which is the point of the exercise: showing the sequence of steps always gives a value of 8.