from GMATprep2

A thin piece wire 40 meters long is cut into two pieces. One piece is used to form a circle radius r,and the other is used to form a square. No wire is left over.which of thr follwing represnts the total area in squre meters of the circular and the square regions in terms of r? Pai*(r^2) Pai*(r^2)+1...

from GMATprep

Circular gears P and Q start roating at the same time at constant speeds.gear P makes 10 revolutions per minute and gear Q makes 40 revolutions per minute.
How many seconds after the gears start roating will gear Q have made exactly 6 more revolutions then gear p?

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12

from gmatprep

If k is a positive integer and the tens digit of k+5 is 4, what is the tens digit of k

1. k>35
2.the unit sigit of k is greater then 5


why is
2