Page 530 - Basic College Mathematics with Early Integers

READING PICTOGRAPHS, BAR GRAPHS, Objectives
7.1 HISTOGRAMS, AND LINE GRAPHS
Read Pictographs.

Often data are presented visually in a graph. In this section, we practice reading sev- Read and Construct Bar Graphs.
eral kinds of graphs, including pictographs, bar graphs, and line graphs.
Read and Construct Histograms.

Objective Reading Pictographs Read Line Graphs.

A pictograph such as the one below is a graph in which pictures or symbols are
used. This type of graph contains a key that explains the meaning of the symbol
used.An advantage of using a pictograph to display information is that comparisons
can easily be made. A disadvantage of using a pictograph is that it is often hard to
tell what fractional part of a symbol is shown. For example, in the pictograph below,
Chinese shows a part of a symbol, but it’s hard to read with any accuracy what frac-
tional part of the symbol is shown.

Example 1 Calculating Languages Spoken PRACTICE 1
Use the pictograph shown
The following pictograph shows the top eight most-spoken (primary) languages. in Example 1 to answer the
Use this pictograph to answer the questions. following questions:
a. Approximate the number of
people who primarily speak
Top 8 Most-Spoken English.
(Primary) Languages b. Approximate how many
more people primarily speak
Bengali
English than Portuguese.
Chinese
English
Hindu 50 million speakers
Japanese
Portuguese
Russian
Spanish

Source: www.ethnologue.com

a. Approximate the number of people who primarily speak Russian.
b. Approximate how many more people primarily speak Spanish than Russian.

Solution:
a. Russian corresponds to 3 symbols, and each symbol represents 50 million
speakers.This means that the number of people who primarily speak Russian is
#
approximately 3 (50 million) or 150 million people. This can also be written as
150,000,000 people.
1 1
b. Spanish shows 3 more symbols than Russian.This means that 3 # (50 million)
2 2
or 175 million or 175,000,000 more people primarily speak Spanish than Russian.
Answers
Work Practice 1 1. a. 300 million or 300,000,000 people
b. 125 million or 125,000,000 people
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