Question 20

Explanation

Let the price of one item $x$ be $x$ and the price of one item $y$ be $y$. The purchases give the following system.

Eliminate $y$ by multiplying the first equation by $2$.

Substitute $x$ into the first equation.

Japri pays $x + y$.

Thus, the required payment is $\text{Rp }1,250.00$.