GMAT math thinking skills 2

Topic: Geometry

Question Type: data sufficiency

To understand directions watch this video

The question is

What is the area? we need a numerical answer. We need some numbers to work with.

Statement 1:  AG:GE = 2:1, A ratio. No numbers. Hence not sufficient

Statement 2: AB = 10 BC= 20. Do we know the nature of the triangle (equilateral or isosceles?) no

We know that AD and BE are the two medians. The medians bisects the base into two equal parts.

The median bisects the triangle into two smaller triangle with equal areas.

 Area of triangle ABD = Area of triangle ADC

Also area of triangle ABE = Area of triangle BEC

G is the centroid so the AG: GD = 2:1 and BG:GE = 2:1

Nothing further can be arrived at. Hence statement 2 is insufficient

Let us combine both statements .. You should know what apollinius theorem is