Respuesta :

Answer:

261 stairs

Step-by-step explanation:

If David trips twice every 9 stairs and he has tripped 58 times. We can multiply 9 by 58.

58*9=522

Since David trips twice in 9 stairs, then to find how many stairs he has climbed we need to divide 522 by 2.

522/2=261

David has climbed 261 stairs.