Some computers at a certain company are Brand X and the rest are Brand

Question

Some computers at a certain company are Brand X and the rest are Brand Y. If the ratio of the number of Brand Y computers to the number of Brand X computers at the company is 5 to 6, how many of the computers are Brand Y?

(1) There are 80 more Brand X computers than Brand Y computers at the company.
(2) There is a total of 880 computers at the company.

Bunuel · Accepted Answer

SOLUTION

Some computers at a certain company are Brand X and the rest are Brand Y. If the ratio of the number of Brand Y computers to the number of Brand X computers at the company is 5 to 6, how many of the computers are Brand Y?

Given that  \frac{y}{x}=\frac{5}{6}  we need to find the value of y.

(1) There are 80 more Brand X computers than Brand Y computers at the company -->  x = 80 + y . We have two distinct linear equations ( \frac{y}{x}=\frac{5}{6}  and  x = 80 + y ) with two unknowns, thus we can solve for both. Sufficient.

(2) There is a total of 880 computers at the company -->  x + y=880 . We have two distinct linear equations ( \frac{y}{x}=\frac{5}{6}  and  x + y=880 ) with two unknowns, thus we can solve for both. Sufficient.

Answer: D.

aeglorre · Answer

We're given: X + Y = Total Computers and 5Y = 6X, with this we can solve for X or for Y.. SO, we only need to solve for ONE variable to answer the question

1) Solves for X and Y given our second equation. Thus, this is sufficient.
2) Solves for TC, thus, this is sufficient since we have a fixed relation between the # of X to Y computers.

So, the answer is D.

anilisanil · Answer

I don't think this is of 650 difficulty level. Even the question statistics say so

RSOHAL · Answer

Given Y:X = 5:6

Y = 5x/6

Statement I:
 
x-80 = y
y = 5(y+80)/6 = 400 Sufficient

Statement II:

y = 5(880-y)/6 Sufficient.

Correct answer is D.

ScottTargetTestPrep · Answer

Solution:

Question Stem Analysis:

We need to determine the number of Brand Y computers at a certain company, given that the ratio of the number of brand Y computers to the number of Brand X computers at the company is 5 to 6. That is, if let the number of Brand Y computers be y, then the number of Brand X computers is 6y / 5 (notice that y / (6y/5) = 5/6). We need to determine the value of y.

Statement One Alone:
 
We can create the equation:

y + 80 = 6y/5

80 = y/5

400 = y

Statement one alone is sufficient.

Statement Two Alone:

We can create the equation:

y + 6y/5 = 880

11y/5 = 880

y/5 = 80
 
y = 400

Statement two alone is sufficient

Answer: D

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Some computers at a certain company are Brand X and the rest are Brand

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