To solve the equation, we need to isolate the variable x.

First, let's simplify the equation:

3(25/4)x - 1.9 = 13/0.3
75x/4 - 1.9 = 43.3333

Now, let's add 1.9 to both sides:

75x/4 = 45.2333

Next, multiply both sides by 4 to get rid of the fraction:

75x = 180.9333

Now, divide both sides by 75 to solve for x:

x = 180.9333 / 75
x = 2.4124

Therefore, the solution to the equation is x = 2.4124.