"What is the minimum size inverse time breaker needed to protect a feeder with "TW" insulation supplying two 1hp single-phase 115V motors?"

This is what I have come up with so far:

1. FLC = 16A (Table 430.148)

2. Overload heater sized at:

16A x 1.15% = 18.4A rated heater 430.32 (B,1)

3. Branch circuit wire size:

16A x 1.25 = 20A # 14 TW Table 316.10

4. Branch circuit OCP:

16A x 2.50 = 40A ocp 430.52, Table 430.52

5. Feeder wire size:

16A x 1.25 = 20A + 16A = 36A # 8 TW 430.24, Table 310.16

This is where I lose my train of thought. Is this method correct?

6. Feeder OCP (using inverse time breakers):

16A x 2.50 = 40A + 16A = 56A but this is a motor feeder so I need to down size to a 50A ocp??? 430.62, 240.4 (G)

Is the math in step six the correct method? Any help would be great.

Thank,

Kevin