On one side of the two-arm scale, there is one weight weighing 0.5 kilograms (kg) and two weights weighing 0.3 kilograms (kg). How many kilograms (kg) must a book weigh in order to make the scale horizontal when this book is placed on the other side?
0.5 0.3 2 [OP_MUL] [OP_ADD]
var_a = 0.5
var_b = 0.3
var_c = 2
var_d = var_b * var_c
var_e = var_a + var_d
print('{:.2f}'.format(round(var_e+1e-10,2)))