Question

Add 15 to a number, then multiply the result by 3. The answer is the same as subtracting 4 from the number and multiplying the result by 5. Find the number.

a) 3
b) 7
c) 9
d) 12

Answer 1

To find the number, set up and solve algebraic equations based on the given information.

Step-by-step explanation:

To solve this problem, let's use algebra to represent the unknown number. We'll call it 'x'. We can set up two equations based on the information given:

Equation 1: (x + 15) * 3 = x * 5 - 4

Equation 2: 3x + 45 = 5x - 4

From here, we can solve for 'x' by simplifying and rearranging the equation. After solving, we find that 'x' is equal to 9. Therefore, the answer is c) 9.