What is fuel oil mix for the mantis rototiller?

Mixing Fuel
Your MANTIS Tiller is powered by
a commercial two stroke, air cooled
engine which requires a fuel mixture
of gasoline and lubricating oil.
Use a mixture of 50 parts unleaded
regular gasoline and 1 part two-stroke
MANTIS oil (50:1.) Use branded 89 octane (R+M+2) unleaded gasoline
or gasohol (maximum 10% ethyl alcohol, or 15% MTBE, no methyl
alcohol.)