Final answer:
To find the number of ladder steps made, subtract the length of wood used for the steps from the total length of wood available. The student has used 3/4 of a foot of wood per step. By solving the equation, it can be determined that the student made 4 ladder steps.
Step-by-step explanation:
To find the number of ladder steps made, we need to subtract the length of wood used for the steps from the total length of wood available. The student has used 3/4 of a foot of wood per step. We can set up an equation to solve for the number of steps:
18 - (3/4) * x = 15
Where x represents the number of steps.
To solve the equation, we can first multiply 3/4 by x. This gives us:
18 - (3/4) * x = 15
4 * (18 - (3/4) * x) = 4 * 15
72 - 3x = 60
Next, we can subtract 72 from both sides:
72 - 3x - 72 = 60 - 72
-3x = -12
Finally, we can divide both sides by -3 to solve for x:
x = -12 / -3
x = 4
Therefore, the student has made 4 ladder steps.