Guys i realyy dont understand the last part of this equation that is the Total revenue part... i understood how v got 100 +x but i really dont understand the change n 2007's total revenue... Its 4m MGMAT FDPs
unable to understand dis equation
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Please post the original question from next time. It is very difficult to get any idea from the solution approach only. Anyways, here is the original question for the help of others,
Hence, the total revenue in 2006 = $(100 + x)
Now, in 2007, the revenue from pen sales = $(100 + 5% of 100) = $105
And revenue from pencil sales = $(x - 13% of x) = $0.87x
Hence, the total revenue in 2007 = $(105 + 0.87x) [This is one way to get overall revenue of 2007]
But, the question said that "overall revenue was down 1% from 2006 to 2007".
Hence, total revenue in 2007 = (0.99)*(Total revenue in 2006) = $(0.99)*(100 + x) [This is another way to get overall revenue of 2007]
Hence, (0.99)*(100 + x) = (105 + 0.87x)
-----> 99 + 0.99x = 105 + 0.87x
-----> (0.99 - 0.87)x = (105 - 99)
-----> 0.12x = 6
-----> x = 50
Hence, ratio of pencil revenue to pen revenue in 2006 = x/100 = 50/100 = 1/2
From the screenshot you posted, it is evident that the book assumed in 2006, the revenue from pen sales was $100 and revenue from pencil sales was $x.A company sells only pens and pencils. The revenue from pen sales in 2007 was up 5% from 2006, but the revenue from pencil sales declined 13% over the same period. If overall revenue was down 1% from 2006 to 2007, what was the ratio of pencil revenue to pen revenue in 2006?
Hence, the total revenue in 2006 = $(100 + x)
Now, in 2007, the revenue from pen sales = $(100 + 5% of 100) = $105
And revenue from pencil sales = $(x - 13% of x) = $0.87x
Hence, the total revenue in 2007 = $(105 + 0.87x) [This is one way to get overall revenue of 2007]
But, the question said that "overall revenue was down 1% from 2006 to 2007".
Hence, total revenue in 2007 = (0.99)*(Total revenue in 2006) = $(0.99)*(100 + x) [This is another way to get overall revenue of 2007]
Hence, (0.99)*(100 + x) = (105 + 0.87x)
-----> 99 + 0.99x = 105 + 0.87x
-----> (0.99 - 0.87)x = (105 - 99)
-----> 0.12x = 6
-----> x = 50
Hence, ratio of pencil revenue to pen revenue in 2006 = x/100 = 50/100 = 1/2
Anju Agarwal
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There is a simple way to solve such (weighted average) questions.
Go thru the file attached with this post
Regards,
Abhijit.
PS :- As advised by Anju, Please post whole question along with all answer choices for better understanding and reply.
Go thru the file attached with this post
Regards,
Abhijit.
PS :- As advised by Anju, Please post whole question along with all answer choices for better understanding and reply.
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This is a MIXTURE problem.A company sells only pens and pencils. The revenue from pen sales in 2007 was up 5% from 2006, but the revenue from pencil sales declined 13% over that same period. If overall revenue was down 1% from 2006 to 2007, what was the ratio of pencil revenue to pen revenue in 2007?
Percent change for pen revenue = +5%.
Percent change for pencil revenue = -13%.
Percent change for the MIXTURE of pen revenue and pencil revenue = -1%.
To calculate the ratio of pen revenue to pencil revenue in the mixture, use ALLIGATION.
Step 1: Plot the 3 percentages on a number line, with the percentages for pens and pencils (+5% and -13%) on the ends and the percentage for the mixture (-1%) in the middle.
Pens (+5%)-----------(-1%)------------(-13%) Pencils
Step 2: Calculate the distances between the percentages.
Pens (+5%)-----6-----(-1%)-----12-----(-13%) Pencils
Step 3: Determine the ratio in the mixture.
The ratio of pen revenue to pencil revenue is the RECIPROCAL of the distances in red.
Pen revenue : pencil revenue = 12:6 = 2:1.
Since the question stem asks for the ratio of pencil revenue to pen revenue, the correct answer is [spoiler]1:2[/spoiler].
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I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
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For more information, please email me (Mitch Hunt) at [email protected].
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