Respuesta :

18, because cats would be 3, and then the dogs would be 6 times that, which would be 18.  18 + 3 = 21.

Answer: There are 18 dogs.

Step-by-step explanation:

Let x be the number of cats.

Given : There are 6 times as many dogs as cats.

Number of dogs = 6x

If the total number of dogs and cats is 21, then we have

[tex]x+6x=21\\\\\Rightarrow\ 7x=21[/tex]

We divide both sides by 7 , we get

[tex]x=3[/tex]

Now, number of cats = 3

Number of dogs = 6(3)=18

Hence, there are 18 dogs.