I'm no good at pastry, but want to make a lemon meringue pie with a biscuit base. What ratio of biscuit to butter do i need?

you need 225g/8oz digestive biscuits (crushed) and 5og/2oz butter or margarine (melted).

put the crushed biscuits in a mixing bowl, add the melted fat and then mixit up. pressit firmly into the base of your flan dish otr whatever else you're using.