Question

ernesto baked 3 cakes in 2.5 hours. assume that the number of cakes baked varies directly with the number of hours. write and solve a direct variation equation to find how many cakes can he bake in 7.5 hours.

Answer 1

You would set up the equation like this:
`3=k(2.5)` where k is the constant of proportionality. Solve for k. k= 1.2. Now, to find how many cakes he can bake in 7.5 hours, set up the equation like this:
`c=1.2(7.5)` . He can bake 9 cakes in 7.5 hours.

Answer 2

Answer: He can bake 9 cakes in 7.5 hours.

Explanation:

Given : Ernesto baked 3 cakes in 2.5 hours.

Ratio of number of cakes time =
`(3)/(2.5)` (1)

Let x be the number of cakes made in 7.5 hours.

Then, Ratio of number of cakes time =
`(x)/(7.5)` (2)

We assume that the number of cakes baked varies directly with the number of hours.

Then from (1) and (2), we have

`(x)/(7.5)=(3)/(2.5)`

Multiply 7.5 on both the sides, we get

`x=(3)/(2.5)*7.5=9`

Hence, he can bake 9 cakes in 7.5 hours.