The traffic that passes through a certain location is composed

Question

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The traffic that passes through a certain location is composed exclusively of the following nonoverlapping types of vehicles: “rural cars,” “urban cars,” “business day trucks,” and “through trucks.” For each of these vehicle types, and for each hour of the day, the graph depicts the typical percentage of the total number of the given type of vehicle passing through the location during that hour. For example, the graph indicates that slightly less than 8 percent of all urban cars that pass through the location on a typical day do so during hour 9.

On the basis of the given information, select from each of the drop-down menus the option that makes the statement most accurate.

On the basis of the given information, select from each of the drop-down menus the option that makes the statement most accurate.

From hour 17 to hour 22, the percent change in number of business day trucks passing through the location  GRAPH_1_PLACEHOLDER .

Assuming that total traffic over the day is the same for each of the four vehicle types, the hour of maximum total traffic is  GRAPH_2_PLACEHOLDER .

ID: 100352

chetan2u · Answer

What we should know: The sum of all the points on each of the line should add up to 100. For example, tak ethe case of through trucks, the dotted orange lines. All 24 points are close to 4%, so they will add up to something greater than 24*4 or 96%.

1. From hour 17 to hour 22, the percent change in number of business day trucks passing through the location  
Since the % on each line has the same base, the number of business day trucks, say b in total, will result in 
 At hour 17:  5%, so  \frac{5}{100}*b = 0.05*b 
 At hour 22:  2.1%, so  \frac{2.1}{100}*b = 0.021*b 
Change = (0.05 - 0.021)b ~ 0.03b
 % change  =  \frac{0.03b}{0.05b}*100=\frac{3}{5}*100  =   60

2. Assuming that total traffic over the day is the same for each of the four vehicle types, the hour of maximum total traffic is  
So, 100% of each is equal, meaning each of the % refers to same total quantity.
We should just check for the options given.
 Hour 9:  (4+5+6.8+7.8)% = 23.6%
 Hour 15:  (3.9+6.4+6.8+7.2)% = 24.3%
  Hour 16:   (4+6+7.3+8.1)% =  25.4%

D3N0 · Answer

A) the percent change in the number of business-day trucks passing through the location from hour 17 to hour 22
Day 17 = 5%, Day 22 = approx 2.1%
%Change (from 17 to 22)=  *100 = 60%

B. Assuming that total traffic over the day is the same for each of the four vehicle types, the hour of maximum total traffic is? 
We have options 9, 15, and 16. We can either add all the hours from the graphs for these options or compare the difference in the percentage change for these different hours. Both ways will give us 16 hr as answer.

Gmatfocus123* · Answer

I took 3:37 minutes to solve this. Is it normal ?

D3N0 · Answer

took me 4 mins. My mistake was reading it in a hurry which had me end up solving the wrong question. I think 1 min spent in reading can help us save time while solving. Just my take

Katyayaniss · Answer

For Q1 - the answer should rather be cannot be determined . Since there is no information shared on the traffic at any hour being the same . We cannot assume it to be constant and hence it has to be cannot be determined

cheshire · Answer

you just take the two y values at 17 and 22 and find the % decrease. I'm not sure what you mean here.

Aboyhasnoname · Answer

Well Let's see if its the right way, took me 2:41 seconds. 
Hour 17 - around 5% - Hour 22 - Around 2% 
So 50% decrease would be 2.5% its more than 50% so 60% decrease

Second one was trickier, but if we see that there is a close fight between 15 and 16...While Trucks are roughly the same..lets focus on the other 3.... 
We can see that its between 6.5 to 7.5..Lets assume safe side 7...so 7 X 3 is 21....for 15th hours..lets go to 16th hour...the business day trucks is on 6th while the other two go to above 7 and above 8..certainly this is more..as its graph is increasing more steeply...and the business day truck graph just went down a litte bit...to add on to this..we see trucks also increased slights from 15th hour to 16th hour....so thats it..16th hour....

PocusFocus · Answer

3:23 also thinking on ways so solve it faster..

bananachips · Answer

Why are we considering that the bases will be the same - we don't know if the traffic is the same for each hour.

Bunuel · Answer

For the second question, the statement itself tells us to assume that the total traffic over the day is the same for each of the four vehicle types. That means the same number of rural cars, urban cars, business day trucks, and through trucks pass through the location in a day. So if we imagine each type has 100 vehicles total, then the graph’s percentages directly give us how many of those 100 appear in each hour.

The traffic that passes through a certain location is composed

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The traffic that passes through a certain location is composed

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