Dint get this question structure

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Dint get this question structure

by [email protected] » Tue Dec 24, 2013 6:29 pm
I find this confusing why is it structured this way? And under which category of questions does this come?
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by Uva@90 » Tue Dec 24, 2013 8:07 pm
Hi Shibsriz,

Is Ans: B ?

Points to Note:
d = 3 when Total Price is 0<x<100
d= 3+ (x-100)/100 when Total Price is 100<x<500
d= 7 when Total Price is >500

George places two Orders.

To Find: Sum of the two Total Price is >499

Statement 1:
For one Order d = 3 so it means Total price of one order is <100
No Information about second order is said.
Hence Insufficient.

Statement 2: d1,d2 = Deliver price of first and second Order.
d1+d2 =10
So order should definitely be >500
we can split into any way ,like d1=5 and d2 =5 or d1= 7 d2=3
Ir-respective of howsoever we split, we will get Sum of Total price of two order must be >499
Hence Sufficient.

Ans is B

Regards,
Uva.
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by Mike@Magoosh » Fri Dec 27, 2013 7:22 am
[email protected] wrote:I find this confusing why is it structured this way? And under which category of questions does this come?
Dear shibsriz,
I'm happy to respond. :-)

This question is about something in math known as a piecewise function. These are studied in advanced Precalculus and Calculus classes. I would say it's a little beyond anything the GMAT would give, except as a really advanced 800+ level problem.

Uva@90 gave a good response. Statement #1 is definitely not sufficient by itself.

For statement #2, if the shipping costs for the two orders are d = 3 and d = 7, the latter would have a price over $500. Suppose the two shipping costs are d = 5 and d = 5. What is the price of the merchandise, x, when d = 5?

d = 5 = 3 + (x - 100)/100
Multiply by 100
500 = 300 + (x - 100)
200 = x - 100
300 = x

So, if each order has a shipping cost of d = 5, then each order has a merchandise cost of x = $300, and the combined cost is $600. Because the function is a linear function, it turns out that if we increase one d above 5, and reduce the other d below 5 by the same amount, the sum of the merchandise costs will remain $600. To see that requires tremendous intuition about the nature of functions. Once again, we are in territory here well beyond what the GMAT typically tests.

Here's a blog you may find helpful:
https://magoosh.com/gmat/2013/mathematic ... -the-gmat/

Let me know if you have any further questions.
Mike :-)
Magoosh GMAT Instructor
https://gmat.magoosh.com/