In a 10 horse race - if I select two horses in the same race to run either 1st , 2nd or 3rd what are the odds of

- one of the horses finishing 1st , 2nd or 3rd

- both horses finishing in the top 3 positions

I've actually got myself completely confused !!

Obviously this is without taking into account the market odds of the horse winning - eg. assume that every horse has an equal chance