Answer: The required number of ounces that he can buy with $1 is 1.25.
Step-by-step explanation: Given that Jackson bought 5 ounces of raisins for $4.
We are to find the number of ounces of raisins that he can buy with $1.
We will be using the UNITARY method to solve the problem.
We have
Number of ounces of raisins that can be bought with $4 = 5.
Therefore, the number of ounces of raisins that can be bought with $1 is given by
[tex]\dfrac{5}{4}=1.25.[/tex]
Thus, the required number of ounces that he can buy with $1 is 1.25.