Guadalupe owns 2 rectangular tracts of land. One is 300 m by 500 m and

Question

Guadalupe owns 2 rectangular tracts of land. One is 300 m by 500 m and the other is 250 m by 630 m. The combined area of these 2 tracts is how many square meters?

A. 3,360 
B. 307,500 
C. 621,500 
D. 704,000 
E. 2,816,000

Shrivathsan · Answer

One is 300 m by 500 m and the other is 250 m by 630 m :

(300*500)+(250*630) = 150000+157500
307500 --> B

adkikani · Answer

niks18   chetan2u   Bunuel   gmatbusters   pushpitkc   VeritasPrepKarishma

Any tips on reducing steps and performing minimal steps to reduce 
calculation errors?

GMATBusters · Answer

In this question, you need to find the area of two rectangular land.
So simply add the area of two rectangle. 
 Area of rectangle = Length * Width

As the dimension of first is 300*500 = we get 150000 ( 4 zeros at end)
other second land is 250*630 = XXXX00 ( 2 zeros at end)
So when we add these, the answer should have 2 zeroes at end. hence options A, D, E are eliminated.

Also 25*60= 1500. So area of second land area is slightly greater than 150000
So sum is slightly greater than 150000+150000 = 300000. Since C is very large compared to this value.

Answer is C

adkikani

KarishmaB · Answer

Total Area = (300*500 + 250*630) = 250*30*(20 + 21) = 7500 * 41 = 307500

(multiply 75 by 41 such that 75 times 1 is 75 so write 5 and carry over 7. Then 75 times 4 is 300 so write 307)

Salsanousi · Answer

Allow me to help even though it is late

500 * 300 = 5 * 3 = 15 then add the zeros, it will be 150,000 now we are clear on one part.

For the other part you could do halving and doubling trick you know 630 * 250 = 315 * 500 , so this will be very close to the number above and the only answer choice that is close to 300,000 is B.

I hope this helps!

Scuven · Answer

I reasoned in this way - If you look at 300 x 500 x 250 x 630 you see that 300 is a multiple of 3. Thus the whole multiplication must be a multiple of 3 and thus the result must be divisible by three. If you look at the options only B can be divided by 3.

CEdward · Answer

3 x 5 = 15 ---> 150000 <--- Add 4 zeros
2 x 6 = 12 ---> 120000 <--- Add 4 zeros

Total area is 150k + 120k = 270k <--- However, since I rounded down, the area should be larger then this.

B.

The key learning here is DO NOT carry out the computation, but approximation problem. This is a 15 second problem.

Excellent problem.

ScottTargetTestPrep · Answer

Solution:

The total area of the 2 tracts, in square meters, is:

300 x 500 + 250 x 630 = 150,000 + 157,500 = 307,500.

Answer: B

ThatDudeKnows · Answer

Ballpark, my dude!!

The first tract is 300x500. That's easy peasy. 15 with four zeros after it. 150,000. Compare the first and second tracts. The second one is a touch smaller than the first in one dimension and a touch larger in the other dimension, so its area is going to be in the ballpark of the first tract. The combined areas should be somewhere in the neighborhood of 300,000. Now look at the answer choices.

A is wayyyyyyy too small. Wrong.
B is in the ballpark. Keep it.
C is four times the size of the first tract. Too big. Wrong.
D is even bigger than C. Wrong.
E is even bigger than D. Wrong.

Answer choice B.

ThatDudeKnowsBallparking

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Guadalupe owns 2 rectangular tracts of land. One is 300 m by 500 m and

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