Basic Engineering Mathematics, Fifth Edition

292 Basic Engineering Mathematics

Now try the following Practice Exercise

PracticeExercise 123 Presentation of

ungrouped data (answers on page 352)

1. The number of vehicles passing a stationary
   observer on a road in six ten-minute intervals
   is as shown. Draw a pictogram to represent
   these data.

Period of time 1 2 3 4 5 6

Number of

vehicles 35 44 62 68 49 41

2. The number of components produced by a
   factory in a week is as shown below.

Day Mon Tues Wed Thur Fri

Number of

components 15802190184023851280

Show these data on a pictogram.

3. For the data given in Problem 1 above, draw
   a horizontal bar chart.


4. Present the data given in Problem 2 above on
   a horizontal bar chart.


5. For the data given in Problem 1 above,
   construct a vertical bar chart.


6. Depict the data given in Problem 2 above on
   a vertical bar chart.


7. A factory produces three different types of
   components. The percentages ofeach of
   these components produced for three one-
   monthperiods are as shown below. Show this
   information on percentage component bar
   charts and comment on the changing trend
   in the percentages of the types of component
   produced.

Month 1 2 3

ComponentP 20 35 40

ComponentQ 45 40 35

ComponentR 35 25 25

8. A company has five distribution centres and
   the mass of goods in tonnes sent toeach

centre during four one-week periods is as

shown.

Week 1 2 3 4

CentreA 147 160 174 158

CentreB 54 63 77 69

CentreC 283 251 237 211

CentreD 97 104 117 144

CentreE 224 218 203 194

Use a percentage component bar chart to pre-

sent these data and comment on any trends.

9. The employees in a company can be split
   into the following categories: managerial 3,
   supervisory9, craftsmen 21, semi-skilled67,
   others 44. Show these data on a pie diagram.


10. The way in which an apprentice spent his
    time over a one-month period is as follows:
    drawingoffice44hours,production64hours,
    training 12 hours, at college 28 hours. Use a
    pie diagram to depict this information.


11. (a) With reference to Figure 31.5, determine
    the amount spent on labourand materials
    to produce 1650 units of the product.
    (b) If in year 2 of Figure 31.4 1% cor-
    responds to 2.5 dwellings, how many
    bungalows are sold in that year?


12. (a) If the company sells 23500 units per
    annum of the product depicted in
    Figure 31.5, determine the cost of their
    overheads per annum.
    (b) If 1% of the dwellings represented in
    year 1 of Figure 31.4 corresponds to
    2 dwellings, find the total number of
    houses sold in that year.

31.3 Presentation of grouped data

When thenumber of members in aset is small,say ten or

less, the datacan be represented diagrammatically with-

out further analysis, by means of pictograms, bar charts,

percentage components bar charts or pie diagrams (as

showninSection31.2).

For sets having more than ten members, those mem-

bers having similar values are grouped together in