Robots X, Y, and Z

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Robots X, Y, and Z

by ska7945 » Fri Aug 22, 2008 11:25 pm
Robots X, Y, and Z each assemble components at their respective constant rates. If rx is the ratio of robot X’s constant rate to robot Z’s constant rate and ry is the ratio of robot Y’s constant rate to robot Z’s constant rate, is robot Z’s constant rate the greatest of the three?
(1) rx < ry
(2) ry < 1

oa c
let's beat GMAT.
Source: — Data Sufficiency |

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by pranavc » Sat Aug 23, 2008 12:17 pm
OK. I would have picked C if I knew a little more about the constant rates of X and Y. Why is E wrong?

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by carefreeamit » Sun Aug 24, 2008 10:37 pm
Both a and b are not sufficient in themselves.

If ry < 1 then rate of z is greater than rate of y. From 1, we already know that rate of x is less than rate of y. So rate of x is less than rate of z too.

Ans C