Multi Bets (also known as All Ups, Parlays or Accumulators) allow you to π combine up to 25 different individual bets into one single bet, with each individual bet being referred to as a π leg. When placing a multi bet you are able to select runners to either win, place and even select the π each-way market.
Racing Multi Bets - Sportsbet Help Centre
A Quinella is a good bet to take when there is a reasonable π sized field ( i.e. 10 runners or more) and you are undecided about a couple of horses. The expected dividend π in a Quinella is generally bigger than taking those same runners in a Win or Place bet. For R$3 you π can pick 3 horses to run 1st and 2nd in any order.