For each question, show all your working in full, as this will be marked, and then write your answer clearly in the space provided.
You have 1 hour for this paper which is worth 80 marks.
The first six questions on this paper are each worth 5 marks.
5. In an IFTHEN sequence, the next number in the sequence is determined by a rule which depends on the previous number.
So for the following rule IF the number is odd THEN add 1 to it,
but IF the number is even THEN add 3 to it
then if the sequence starts with 3, it will continue after 3 as follows
4, 7, 8, 11 and so on.
List the next four numbers after the starting number in each of the following IFTHEN sequences by applying the rules given
(a) IF the number is odd THEN multiply by 2,
but IF the number is even THEN subtract 1.
Starting number of sequence is 3
(b) IF the number is greater than 10,
THEN divide by 2, but IF the number
is less than 10 THEN multiply by 3.
Starting number of sequence is 16
(c) IF the number is prime THEN add 5, but IF the number is not prime
THEN divide by 2.
Starting number of sequence is 11
The remaining longer problems on this paper are each worth 10 marks.
(e) Word got round amongst the sharks that there was a good
meal to be had in this part of the sea! During the day there is
still a 50% increase in the number of fish, but if 15 sharks
came each night, eating 300 fish each, complete the table below.