Gmat practice test 1

just find the area of 2 triangles.

Pqr=1/2 b.h
1/2 (4)* 4= 8

lmn=1/2 b.h
1/2 (12)* 12)=72

so 8/72= 1/9
A

somehow I am getting ans 1/3.
What's OA

OA is 1/9

it was posted on forum sometime back with the picture.

mental wrote:OA is 1/9

it was posted on forum sometime back with the picture.

I cannot find it. Do you have the link.....

I am unable to look for it

anyway will try to give a brief solution

as you see that points L,P,R,N all lie on x-axis

triangle LMN, base = LN = 12 (difference of x-odinates)
height = y-ordinate of m = 12, as the perpencular distance from x-axis
AREA = 12*12/2=72

Triangle PQR, base = PR = 4 (10-6)
height = 4
AREA = 4*4/2=8

ratio = 8/72 = 1/9


...........................
also if you see, they are similar isoceles triangles

also their bases are in ratio 1:3
also heights in 1:3

so area will be 1:9

.......................................
hope that helps

mental wrote:I am unable to look for it

anyway will try to give a brief solution

as you see that points L,P,R,N all lie on x-axis

triangle LMN, base = LN = 12 (difference of x-odinates)
height = y-ordinate of m = 12, as the perpencular distance from x-axis
AREA = 12*12/2=72

Triangle PQR, base = PR = 4 (10-6)
height = 4
AREA = 4*4/2=8

ratio = 8/72 = 1/9


...........................
also if you see, they are similar isoceles triangles

also their bases are in ratio 1:3
also heights in 1:3

so area will be 1:9

.......................................
hope that helps

Thanks a lot.......