Question 301 Data Sufficiency 2018 GMAT Official Guide

Question 301 Data Sufficiency 2018 GMAT Official Guide

Video explanation: The rectangular rug shown in the figure above has an accent…

Comments

Abhisays

I am coming with a conclusion C.
Considering l and b for outer rectangle so from condition 1,
2l+2b=44 which means l+b =22.

Now from condition 2,
length of small rectangle = l-2
Breadth of small rectangle = b-2
area of the portion = l*b-[(l-2)*(b-2)]
= lb- lb+2(l+b)-4
=2(l+b)-4= (2*22)-4
=40
Area of shaded region = 40 which makes C as an answer. Where am I going wrong with this?

They are asking for the area of the portion of the rug that excludes the border, which according to your labeling, is equal to $(l-2)(b-2)$. What you are computing is the area of the accent, or the dark part in the image, which you have indeed computed correctly and a unique value can be obtained if we are given both statements.

I hope this make sense. If not I will make a video explanation.

Abhi says

I am coming with a conclusion C.

Considering l and b for outer rectangle so from condition 1,

2l+2b=44 which means l+b =22.

Now from condition 2,

length of small rectangle = l-2

Breadth of small rectangle = b-2

area of the portion = l*b-[(l-2)*(b-2)]

= lb- lb+2(l+b)-4

=2(l+b)-4= (2*22)-4

=40

Area of shaded region = 40 which makes C as an answer. Where am I going wrong with this?

GMAT Quantum says

Hi Abhi,

They are asking for the area of the portion of the rug that excludes the border, which according to your labeling, is equal to $(l-2)(b-2)$. What you are computing is the area of the accent, or the dark part in the image, which you have indeed computed correctly and a unique value can be obtained if we are given both statements.

I hope this make sense. If not I will make a video explanation.

Dabral