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.
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: He can bake 9 cakes in 7.5 hours.
Step-by-step explanation:
Given : Ernesto baked 3 cakes in 2.5 hours.
Ratio of number of cakes time =\(\dfrac{3}{2.5}\) (1)
Let x be the number of cakes made in 7.5 hours.
Then, Ratio of number of cakes time =\(\dfrac{x}{7.5}\) (2)
We assume that the number of cakes baked varies directly with the number of hours.
Then from (1) and (2), we have
\(\dfrac{x}{7.5}=\dfrac{3}{2.5}\)
Multiply 7.5 on both the sides, we get
\(x=\dfrac{3}{2.5}\times7.5=9\)
Hence, he can bake 9 cakes in 7.5 hours.