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neokeynesian
11-20-2004, 01:21 AM
Please see the attachment.

danielman
11-20-2004, 02:43 AM
Hi!
Q1) You have to remember that in general the ratio of areas is the ratio of linear dimentions but *squared*

A) 4*Area(circle with radius r) = 4*pi*r^2
B) Area (circle with radius 2r) = pi*(2r)^2 = pi*4*r^2

thus A = B.
Note also that you don't even need to calculate those areas, only to notice that the ratio (radius A) : (radius B) = 1:2, so (area circle A) : (area circle B) = 1:4

Q2) You just have to follow the instructions! :) Because they are asking for a proportion, a useful aproach is to assume a total for the class, find the number of absent students and divide that number by the assumed total (the assumed total cancels out after this operation). Let's say there are 6 student in the class:

TOTAL = 6
# girls = 2/3 (TOTAL) = 4
# Boys = TOTAL - #Girls = 2

Absent:
Girls = 1/2(#girls) = 2
Boys = 1/3 (#boys) = 2/3
total absent = 2+2/3

fraction absent = (total absent)/total= 1/6(2 + 2/3)= 4/9

Q3) (I hate DI questions!)
The total number of companies is 300 and they are asking for options that are offered by at least 30 companies which is equivalent to more than 10% of them.

From the graph at the bottom, all but "work at home" are offered by more than 10% of the companies. Hence the answer is 4 (the last bar is not a "flexible schedulling option"!)

Q4) nice question!
The best thing you can do is to draw your own calendar for month X. Assuming that the month begins in a Tuesday, there are seven more days after the 4th Tuesday. So, start thinking: "what if the month would have begun monday? or Sunday?...) you only have seven choices before you ran out of days having the same 4th tuesday.

Hope this helps

neokeynesian
11-20-2004, 05:20 AM
Hi danielman,

thnx so much for the anwers.