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Algebra Difficulty 1.4 Junior Find the answer Canada

In the graph, the five points show the money earned versus time
worked for each of five employees. Each was paid a different but fixed
number of dollars per hour. Which letter represents the employee who was
paid the most money per hour?

Hide/Reveal Description of Diagram for Question 12

A graph with horizontal axis Time (hours) and vertical axis Money
Earned ( $). There are$ 14$ equally
spaced vertical lines, including the vertical axis, and $15$ equally spaced horizontal lines,
including the horizontal axis. Each of the letters $A$ through $E$ marks a point where two lines intersect. Counting horizontal lines from the bottom up and vertical lines from left to right, not including the axes, the letters are located at the following
intersections:

Letter $A$ : 2nd vertical line and 10th horizontal line
Letter $B$ : 4th vertical line and 6th horizontal line
Letter $C$ : 6th vertical line and 12th horizontal line
Letter $D$ : 8th vertical line and 4th horizontal line
Letter $E$ : 10th vertical line and 8th horizontal line

Pick one

Solution

The vertical axis represents money earned (in dollars) and the
horizontal axis represents time (in hours).

Thus, each employee’s money earned per hour is the slope of the line
segment from the origin $(0,0)$ to
the employee’s letter.

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The employee who was paid the most money per hour is the employee
whose line segment has the greatest slope.

The line segment with the greatest slope is the steepest of the $5$ line segments, and so Employee $A$ was paid the most money per hour.

Alternately, we could add numbers to each of the axes and use them to
determine the slope of each line, and thus the money earned per hour for
each employee.

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Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.