Hi!
So, x is going to be the price of one apple. We need to solve for x, so let's start with getting an equation up and running.
3x + 0.84 = 5x
Now, we're going to subtract three from both sides.
3x - 3x + 0.84 = 5x - 3x
Now, we're going to divide 2 from both sides!
0.84 / 2 = 2x / 2
And our final answer is... 0.42 for each apple! =)