if a man travelled by boat from India to Africa in the early 20th century how long would the journey take?

Trying to figure out how long a boat from Gujarat in India to Tanzania in East Africa would have taken about 80 years ago.

Figured out the distance is about 4600KM but no idea on how fast the boat would have travelled. Any ideas?

Sure i have. The man would have died before reaching his destination. But if you neglect all this factors and he travels at a speed of 10 km/hr (above which he cannot go!) and stops every night on an island and wasted 15 days of his journey in collecting food from islands and resting there, he would totally take 1 month and 25 days. It is exact figure!!
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