Two math problems I need help with

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1

<p>1) On each of the days Monday through Friday, Toni spent 1 hour commuting to work and 1 hour commuting back home. What fraction of the total number of hours in these five days did she spend commuting?</p>

<p>A) 1/12
B) 1/24
C) 5/12
D) 5/24
E) 10/168</p>

<p>Answer A but HOW? If she spent 1 hour commuting to work and 1 hour commuting back home for 5 days, that's 10 hours total. So why isn't there an answer in one of the choices with a 10 as its denominator? o_O And the total number of hours she spent commuting total was 10 hours as well? Shouldn't the answer be 10/10 or 1?</p>

<p>2) In a certain game, each token has one of three possible values: 1 point, 5 points, and 10 points. How many different combinations of these token values are worth a total of 17 points?</p>

<p>A) Two
B) Three
C) Four
D) Five
E) Six</p>

2

<p>1 is actually quite simple. It’s just 2 hours a day, which is 2/24, 1/12. It asks for the amount of hours spent community over the total amount of hours in the 5 days. It’s the same for each day, but to make it more simple: 10/(24 x 5) = 1/12.</p>

3

<ol>
<li>5(1+1) = 10. 5*24=120. 10/120 = 1/12</li>
</ol>

<p>Alternatively, you could realize that each of the five days is identical and just consider one day (2/24 = 1/12)</p>

4

<p>2) E
1 x 17
1 x 12 + 5
1 x 7 + 2 x 5
1 x 2 + 3 x 5
1 x 7 + 1 x 10
1 x 2 + 1 x 5 + 1 x 10</p>

5

<p>Could we have used 3! to solve number two?</p>

<p>3! = 3<em>2</em>1 = 6</p>

6

<p>1) She spends 2 hrs a day commuting for 5 days, a total of 10 hours. The total number of hours in 5 days is 5x24 = 120.</p>

<p>10/120 = 1/12</p>

<p>The reason there’s no 10 in the answer choices is because the fractions can be reduced.</p>

<p>2) This one you really have to play around with the tokens to get as many combinations as possible. Mamooie listed them for you.</p>

7

<p>@jamesford: Well, he asked why wasn’t 10 in the denominator (not in the numerator). This is what’s confusing about his reasoning. It probably means he didn’t understand what the question was asking since he believes it is 10/10.</p>