##### ratios and proportions

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A random survey of 400 out of 20000 likely voters found that the ballot measure was favored by 220 people. Based on these results, predict the number of people hwo will vote in favor of the ballot measure.

Apr 16th, 2015

The ratio of the number people in favor of the ballot measure to the total number of people is assumed to be the same both for the sample of 400 voters and for the whole population of 20000 likely voters.

This results in the following proportion: 220/400 = x / 20000, where x is the number of people who will vote in favor of the ballot measure. Cross-multiplication yields x = 220 * 20000 / 400 = 11000.

Apr 16th, 2015

Thanks so much! Really appreciate it!!!

Apr 16th, 2015

You are welcome.

Apr 16th, 2015

So, the red line graphs the equation -2x + 3y = 18 (intercepts x = -9 and y = 6) while the blue line is the graph of the equation x + y = -4. They intersect at the point x = -6, y = 2.

Check: -2*(-6) + 3*2 = 12 + 6 = 18; (-6) + 2 = -4.

Answer: x = -6; y = 2.

Apr 16th, 2015
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Apr 16th, 2015
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Apr 16th, 2015
May 23rd, 2017
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