FROM DATA TO GRAPHS AND VICE VERSA 

3rd year of secondary education. 


1.
PLOTTING GRAPHS AND MORE 

You
can use the parameter
"games" in
this window, to draw a graph
which relates to the activities accompanying it. The plotted graph and the
data given should help you to carry out the activities appropriately. 


1. Imagine that you work as a sales representative for a company that designs computer games. You earn a fixed salary of 300 euros a month plus 3 euros for each game you sell. Which magnitudes are related to each other? Are they all variables? 2. Draw
a table of values in your notebook which shows the salary you earn for different
amounts of videogames sold. Give the amount of games sold in multiples of five
to make it easier. 3. Draw the graph that appears in the window. What type of graph is it? Try and write a formula which allows you to work out in advance how much you will earn in a particular month knowing the number of games sold that month. 
4. How much did you earn last month, given that you sold 347 games? How many games did you sell during a month when you earned 714 euros? 
2. MORE
COMPLEX GRAPHS 

In
this window you will see a more complex graph
that in the window above. To see the graph move point A
along the horizontal
axis. 


5.The
graph that appears in the window represents the following situation:
Some secondary school students have a rope which is 24 metres long. They have
to use it to form rectangles in the school playground. Draw up a table of
values which shows the relationship between the base of a rectangle
and its area. 6. Draw the graph that
appears in your notebook. Mark some of the values given on the axes.
Give a brief description of the graph. 7. Write
a formula that allows you to work out the area of any rectangle given its
base. 

3. VICE
VERSA: THE OTHER WAY AROUND 

Use
point A
in the following window to obtain useful data for the following activities. 




11.If
we had included the standing charge part of the electricity bill, which is
always the same (it covers equipment rental etc), in the table of
values what would the graph have
looked like? 
4.
PLOTTING ANOTHER GRAPH 


The
following window is similar to the previous one. The difference is that the
points that appear correspond to another type of relation
between two variables.
There are some lines
linked together
by points that you also have to use in the following activities. 


12. The following table of values shows the frequency certain radio stations are broadcast on and the wavelength of the signal. Move point A which appears in the window. When the white lines disappear, draw the graph into your notebook. Write down the information given in the table on the appropriate part of the graph.
13.
Place
the points joining the red lines onto the points which appeared in the window.
Draw the result in your notebook. What kind of graph does it remind you of? 

14. Find
an algebraic expression that relates the broadcast frequency with the
wavelength. What is the wavelength of the signal if a certain station
broadcasts on FM on a frequency band of 88.5 MHz (megahertz)?
(1 MHz = 1000 kHz) 



















Josep Mª Navarro Canut 


Spanish Ministry of Education. Year 2001 



Except where otherwise noted, this work is licensed under a Creative Common License