Amateur,

Strike rate is just your number of winners divided by your number of bets expressed as a percentage. For the figures you give we get:

Win Strike Rate = 1/6 = 16.7%
Place Strike rate = 2/6 = 33.3%

So a 70% strike rate would mean 7 wins for every 10 bets - possible with place betting but you will be a millionaire if you can do it on win betting!