The shape of the boat hull, the gearing, the propeller size and pitch, the draught, the tide all influence the speed a vessel will travel.
A 6 hp outboard will go about fast enough to plane a 10 ft. aluminum boat, with one passenger aboard.
About 10 to 12 on plane
About 240 MPH
Answer now.
My Water Skimmer 10 ft boat can go 27 mph. Probably the fastest hull design ever for a small boat. Boat is rated for a 15 hp and that can push the boat well over 30 mph. Unsinkable, glass bottom, replace your dinghy or jet ski. www.WaterSkimmerBoats.com
A 7.5 hp outboard would work for a small, lightweight boat, something along the line of a 10 to 12 ft. aluminum boat.
26 mph
32-37
70
Speed is dependant on a number of factors. Most importantly the size, type and weight of the boat that it is on and the number of people on board. A 50 HP outboard will push a small aluminum fishing boat a lot fast than it will a 20 ft fiberglass boat. I have a 50 HP 2 stroke that will push a 16 foot aluminum boat 35 MPH.
it is very fast
it all depends on water conditions and the boat.the right size boat for a 100 hp should do around 55-60mph