Kathy stood on the middle rung of a ladder. She cimbed up 3 rungs, moved down 5 rungs, and then climbed up 9 rungs. Then she climbed up the remaining 2 rungs to the top of the ladder. How many rungs are there in the whole ladder?

18 rungs

Step-by-step explanation:

Let x = number of rungs

x/2 = middle

Climbed 3

x/2 +3

Down 5  

x/2 +3 -5

Climbed 9

x/2 +3 -5+9

Then climbed 2 more

x/2 +3 -5+9 +2

Now is at the top

x/2 +3 -5+9 +2 =x

Combine like terms

x/2 +9 = x

Subtract x/2 from each side

x/2+9-x/2 = x - x/2

9 = x/2

Multiply each side by 2

18 =x

dont understand

step-by-step explanation: