A box of dog food would feed 5 dogs for 4 days. How long would it feed 8 dogs ?

Cross multiply and solve for x.

5/4 = 8/x

Cross multiplying will not work. It asks to subtract the amount not add it.

To find out how long a box of dog food would feed 8 dogs, we need to set up a proportion using the given information.

The first step is to determine the ratio of dogs to days. We know that a box of dog food is enough to feed 5 dogs for 4 days. So, the ratio of dogs to days would be 5:4.

Now, let's set up the proportion:

5 dogs / 4 days = 8 dogs / x days

To solve for x (the number of days it would feed 8 dogs), we can cross-multiply:

5 * x = 8 * 4

5x = 32

Now, divide both sides of the equation by 5 to solve for x:

x = 32 / 5

x ≈ 6.4

Therefore, a box of dog food would feed 8 dogs for approximately 6.4 days.