Question 3 of 10 (1 point)jump to question:     1  2  3  4  5  6  7  8  9  10  what is the minimum length ladder that a worker needs to access a landing nine feet above the adjacent floor?

12 ft ladder

Explanation:

Generally, for every 4 units of height, a ladder should be a minimum of 1 unit away.  Then, the distance from the base for a ladder of 9 ft height is:

4/9  = 1 /x

x = 9/4 = 2.5 ft

Using the Pythagorean Theorem:  

length of the ladder ² = distance from the base ² + height of the ladder ²

length ² = 2.5² + 9 ²

length = √87.25 = 9.34 ft

The ladder should always extend at least a couple feet beyond the height your are trying to reach.  Then:

9.34 ft + 2 ft = 11.34  ft

Rounding it to the nearest greater integer we get 12 ft