Conditional evaluation

[snippsat]

It does not work for me like this:

There are several error here,should look a some tutorials as these errors are really basic.

a1 =  float(0.1)
b1 =  float(3.4)
silos1a = b1 - a1
if silos1a < 0:
    print(f'Расход: {silos1a:.1f}')
elif b1 - 6553.5 - a1:
    # Should maybe do some stuff here
    print(f'Расход: {silos1a:.1f}')

Output:
Расход111: 3.3