Can you please help explain how to get the answer to 3/x = 2/5

Question

thanks a heap

3/x = 2/5
Multiply both sides by x (to get rid of the x in the denominator)
x*(3/x) = x*(2/5)
3 = 2x/5
Now multiply both sides by 5 (to get rid of the 5 in the denominator.)
3*5 = 5*(2x/5)
15 = 2x
Now divide both sides by 2
15/2 = 2x/2
7.5 = x