1.How much is a half of quarter. 2)Add up all the prime numbers between 20 to 40. 3) How many thirds make 5. 4)A chicken?? needs to be cooked for 20 minutes per 500g,plus an extra 30 minutes.How long would a 3kg ?? need cooking for? 5) I buy a packet of ??.It normally has 600g,but has 20% extra free.How many grams is there in the packet?