Gmat Prep 1

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Gmat Prep 1

by abhinav85 » Tue Jul 14, 2009 5:07 am
At a certain company,the average (airthmetic mean) number of years of experience is 9.8 years for the male employees and 9.1 years for the female employees.What is the ratio of the number of the company's male
employees to the number of the company's female employees?

1.There are 52 male employees at the company.

2.the average number of years of experience for the company's male & female employees combined is 9.3 years.

OAB

I know its easy but got stuck on this.
Source: — Data Sufficiency |

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by sreak1089 » Tue Jul 14, 2009 5:27 am
Let 'x' be no. of male employees and 'y' be no. of female employees.
We know avg exp for male employees is 9.8 and that of female employees is 9.1.

What we need to find is x/y.

stmt # 1: gives us the value the value of x. But we don't know the value of y. So, stmt # 1 is not sufficient.

stmt # 2: says the combined average of male and female is 9.3
=> (9.8x + 9.1y)/(x+y) = 9.3
=> 9.8x + 9.1y = 9.3x + 9.3y
=> 0.5x - 0.2y = 0
=> 0.5x = 0.2y
=> x/y = 2/5

Hence stmt # 2 is sufficient. Answer is B.