#### mardy

1. How many fatal casualties were caused by fires between 2010/11 and 2012/13?
a. 882
b. 129624
c. 782
d. 556
e. 316

2. In 2012/13 how many more fatal casualties occurred in an area where a fire alarm was present than in an area where a fire alarm was absent?
a. 266
b. 177
c. 88
d. 41
e. 86

3. Approximately, how many fatal casualties were there in 2011/12, as a percentage of the total number of fires that year?
a. 2%
b. 6.8%
c. 0.5%
d. 0.7%
e. 4.9%

#### JeffM

We provide HELP, not answers, so you can do future problems.

Let's go one question at a time.

The first question is admittedly not worded as well as possible. One thing you must learn to do is to figure out what a question means because not all are worded perfectly (particularly in real world situations). What this question MEANS is how many fatalities occurred over the periods 2010/11, 2011/12, and 2012/13 combined together. So what should you do to get an answer to that question?

#### mardy

thank you for your help, I'm happy to try and work out the problem, i'm trying to get better at math. I got 882 for the first question, and 88 for the second. However i am stuck on the 3rd, i am not very confident with percentages.

#### mardy

We provide HELP, not answers, so you can do future problems.

Let's go one question at a time.

The first question is admittedly not worded as well as possible. One thing you must learn to do is to figure out what a question means because not all are worded perfectly (particularly in real world situations). What this question MEANS is how many fatalities occurred over the periods 2010/11, 2011/12, and 2012/13 combined together. So what should you do to get an answer to that question?
thank you for your help, I'm happy to try and work out the problem, i'm trying to get better at math. I got 882 for the first question, and 88 for the second. However i am stuck on the 3rd, i am not very confident with percentages.

#### JeffM

thank you for your help, I'm happy to try and work out the problem, i'm trying to get better at math. I got 882 for the first question, and 88 for the second. However i am stuck on the 3rd, i am not very confident with percentages.
882 is not even one of the proposed answers. Did you mean 88? 88 is the correct answer. Why? During 2012/13, there were

$68 + 62 + 47 = 177$ fatalities when an alarm was present and $89$ when an alarm was not present.

You correctly saw that the question asked for how many MORE occurred when an alarm was present:

$177 - 89 = 88.$ Good job UNDERSTANDING the question.

OK Lets move on to question 3. Percents are far easier to do today than before we had calculators. That is, they are easier once you grasp the basic procedure and concept.

The basic procedure is this: we identify a relevant number as a base; we then divide the base into the number of interest, and finally we multiply the resulting quotient by 100 and stick a percent sign at the end. That is the procedure.

So let's do that procedure for this problem.

The phrase "percentage of" identifies what is the base, which in this case is total fires for 2011/12. So base = $43,594.$

The number of interest is "how many fatalities" in that year. So we have $298.$

The INVARIABLE procedure is $\left(100 * \dfrac{298}{43,594}\right)\% \approx 0.68358\% \approx 0.7\%.$

But what does it mean? It means that out of every hundred fires, there is slightly less than one fatality. That is easier for the human mind to comprehend than saying there are only 298 fatalities out of 43,594 fires. We make everything relative to one hundred, which is a familiar and human scale.

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