Answer:
The cost of 1 orange y = 1.1
Explanation:
Let cost of 1 apple = x
Cost of 1 orange = y
We will make equations from given statements to find the cost of 1 orange i.e y
Wilma bought 3 apples and 6 oranges for $9: Mathematical expression will be:

Fernando bought 6 apples and 2 oranges for $7. Mathematical expression will be:

Let:

Multiply eq(1) by 2 and subtract both equations.

So, We get value of y=1.1
Now, put value of y in eq(1) to find value of x

So, the cost of 1 orange y = 1.1