1/3 +1/2 - 5/6 + 1/5 + 1/4 - 9/20 =
A. 0
B. 2/15
C. 2/5
D. 9/20
E. 5/6
The OA is A.
Experts, is there a fast way to solve this? There are many fractions.
1/3 +1/2 - 5/6 + 1/5 + 1/4 - 9/20 =
This topic has expert replies
- DavidG@VeritasPrep
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Split it into two pieces, each of which allows for an easy calculation for your common denominatorM7MBA wrote:1/3 +1/2 - 5/6 + 1/5 + 1/4 - 9/20 =
A. 0
B. 2/15
C. 2/5
D. 9/20
E. 5/6
The OA is A.
Experts, is there a fast way to solve this? There are many fractions.
Piece One: 1/3 + 1/2 - 5/6
3/6 + 2/6 - 5/6 = 5/6 - 5/6 = 0
Piece Two: 1/5 + 1/4 - 9/20
4/20 + 5/20 - 9/20 = 9/20 - 9/20 = 0
0 + 0 = 0. The answer is A
- GMATGuruNY
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Set the equation equal to x and multiply by the LCM of the denominators (60):M7MBA wrote:1/3 +1/2 - 5/6 + 1/5 + 1/4 - 9/20 =
A. 0
B. 2/15
C. 2/5
D. 9/20
E. 5/6
x = 1/3 +1/2 - 5/6 + 1/5 + 1/4 - 9/20
60x = 60(1/3 +1/2 - 5/6 + 1/5 + 1/4 - 9/20)
60x = 20 + 30 - 50 + 12 + 15 - 27
60x = 50 - 50 + 27 - 27
60x = 0
x = 0.
The correct answer is A.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
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As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
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- Brent@GMATPrepNow
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For integers x and y, we can say: 1/x + 1/y = (x + y)/xyM7MBA wrote:1/3 +1/2 - 5/6 + 1/5 + 1/4 - 9/20 =
A. 0
B. 2/15
C. 2/5
D. 9/20
E. 5/6
Applying this property, we get:
1/3 +1/2 - 5/6 + 1/5 + 1/4 - 9/20 = (3 + 2)/(3)(2) - 5/6 + (5 + 4)/(5)(4)- 9/20
= 5/6 - 5/6 + 9/20 - 9/20
= 0
= A
Cheers.
Brent