Explanation:
(a) Your computer may be programmed to allocate borderline cases to the
next group down, or the next group up; and it may or may not manage
to follow this rule consistently, depending on its handling of the numbers
involved. Following a rule which says 'move borderline cases to the next
group up', these are the five classifications.
(i) 1.0-1.2 1.2-1.4 1.4-1.6 1.6-1.8 1.8-2.0 2.0-2.2 2.2-2.4
6 6 4 8 4 3 4
2.4-2.6 2.6-2.8 2.8-3.0 3.0-3.2 3.2-3.4 3.4-3.6 3.6-3.8
6 3 2 2 0 1 1
(ii) 1.0-1.3 1.3-1.6 1.6-1.9 1.9-2.2 2.2-2.5
10 6 10 5 6
2.5-2.8 2.8-3.1 3.1-3.4 3.4-3.7
7 3 1 2
(iii) 0.8-1.1 1.1-1.4 1.4-1.7 1.7-2.0 2.0-2.3
2 10 6 10 7
2.3-2.6 2.6-2.9 2.9-3.2 3.2-3.5 3.5-3.8
6 4 3 1 1
(iv) 0.85-1.15 1.15-1.45 1.45-1.75 1.75-2.05 2.05-2.35
4 9 8 9 5
2.35-2.65 2.65-2.95 2.95-3.25 3.25-3.55 3.55-3.85
7 3 3 1 1
(V) 0.9-1.2 1.2-1.5 1.5-1.8 1.8-2.1 2.1-2.4
6 7 11 7 4
2.4-2.7 2.7-3.0 3.0-3.3 3.3-3.6 3.6-3.9
7 4 2 1 1
(b) Computer graphics: the diagrams are shown in Figures 1.9 to 1.11