Final answer:
To find the number of cats and dogs, set up a system of equations based on the given information. Solve the equations simultaneously to find the values of x and y. x = 25 and y = 20, so there are 25 cats and 20 dogs in the room.
Step-by-step explanation:
To find the number of cats and dogs, we can set up a system of equations based on the given information.
Let's say there are x cats and y dogs. Each cat takes 7 biscuits, so the total number of biscuits eaten by cats is 7x. Similarly, each dog takes 9 biscuits, so the total number of biscuits eaten by dogs is 9y.
According to the problem, the total number of biscuits eaten by 45 animals is 355. So we can write the equation: 7x + 9y = 355.
We also know that there are a total of 45 animals in the room, so we can write another equation: x + y = 45.
Now we can solve these equations simultaneously to find the values of x and y.
By solving these equations, we find that x = 25 and y = 20. Therefore, there are 25 cats and 20 dogs in the room.