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, 2014

Algebra Difficulty 1.2 Junior Find the answer Canada

At 2 p.m., Sanjay measures the temperature to be $3^\circ$ C. He measures the temperature every hour after this until 10 p.m. He plots the temperatures that he measures on the graph shown.Hide/Reveal Data Table for Graph Time of Day (p.m.) Temperature (℃) 2 3 3 4 4 6 5 8 6 9 7 7 8 4 9 3 10 2 At what time after 2 p.m. does he again measure a temperature of $3^\circ$ C?

Pick one

Solutions — 2

Solution 1

The line representing a temperature of $3^\circ$ is the horizontal line passing halfway between $2^\circ$ and $4^\circ$ on the vertical axis.

There are two data points on this line: one at 2 p.m. and one at 9 p.m.

The required time is 9 p.m.

Figure for this problem

Solution 2

The line representing a temperature of $3^\circ$ is the horizontal line passing halfway between $2^\circ$ and $4^\circ$ on the vertical axis.

There are two data points on this line: one at 2 p.m. and one at 9 p.m.

The required time is 9 p.m.

Figure for this problem

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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.