Answer:
Explanation:
This is a question worth knowing how to do. It is prime candidate for a test question.
Equation
Let the unit be x
therefore
4x + 5x + 6x = 45
Solution
15x = 45
x = 45/15
x = 3
The shortest piece is 4*3 = 12
The middle piece = 5*3 = 15
The longest piece = 6*3 = 18
Total 45