nelz007 wrote:

How many computers did Michael, a salesman for the computer company Digital Electronics Labs, sell this past year that had more than 4GB of RAM and the Microsoft Windows XP operating system? (Michael sold no computers with exactly 4GB of RAM)

(1) 40% of the 200 total computers that Michael sold had XP and less than 4GB of RAM; these computers represent 80% of the total computers that Michael sold with XP.

(2) 50% of the 200 total computers that Michael sold had XP. Of the computers that Michael sold without XP, half had more than 4GB of RAM while the other half had less than 4GB of RAM.

so we are looking for COMPUTERS sold that had>4GB RAM and XP OS..

(1) 40% of the 200 total computers that Michael sold had XP and less than 4GB of RAM; these computers represent 80% of the total computers that Michael sold with XP.Total computers sold = 200,

40% of it so \(\frac{40}{100}*200=80\) had <4GB and XP os

80% of Computers sold with XP os = 80, so computers sold with XP =\(80*\frac{100}{80}=100\)

so BOTH XP and >4GB = 100-80=20

suff

(2) 50% of the 200 total computers that Michael sold had XP. Of the computers that Michael sold without XP, half had more than 4GB of RAM while the other half had less than 4GB of RAM.clearly insuff

A

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