It is currently 20 Jan 2019, 17:01

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# At Didymus Corporation there are just two classes of employe

Author Message
TAGS:
Intern
Joined: 22 Aug 2018
Posts: 26
Followers: 0

Kudos [?]: 4 [1] , given: 4

At Didymus Corporation there are just two classes of employe [#permalink]  20 Sep 2018, 07:33
1
KUDOS
00:00

Question Stats:

87% (01:58) correct 12% (00:04) wrong based on 8 sessions
At Didymus Corporation there are just two classes of employees: Silver and Gold. The average salary of Gold is $56000 higher than that of silver employees. If there are 120 silver employees and 160 gold employees then the average salary for the company is higher than the average salary for the silver by A) 8000 B) 15000 C) 25000 D) 32000 E) 36000 [Reveal] Spoiler: OA Last edited by chetan2u on 12 Jan 2019, 06:28, edited 1 time in total. Formatted the question Moderator Joined: 18 Apr 2015 Posts: 5336 Followers: 84 Kudos [?]: 1092 [0], given: 4955 Re: At Didymus Corporation there are just two classes of employe [#permalink] 20 Sep 2018, 07:50 Expert's post The ratio of silver employees to gold employees is silver : gold = 120:160 = 12:16 = 3:4 If we divide the distance between the two averages by 7, then silver will be “four parts” away from the total average, and gold will be “three parts” away. The difference is$56,000, so that divided by 7 is $8000. That’s one part. Four parts would be$32,000, which has to be the distance from the silver average to the total average.

C
_________________
Intern
Joined: 22 Aug 2018
Posts: 26
Followers: 0

Kudos [?]: 4 [0], given: 4

Re: At Didymus Corporation there are just two classes of employe [#permalink]  20 Sep 2018, 11:32
Carcass wrote:
The ratio of silver employees to gold employees is

silver : gold = 120:160 = 12:16 = 3:4

If we divide the distance between the two averages by 7, then silver will be “four parts” away from the total average, and gold will be “three parts” away.

The difference is $56,000, so that divided by 7 is$8000. That’s one part. Four parts would be $32,000, which has to be the distance from the silver average to the total average. C How can we take the algebraic approach? Moderator Joined: 18 Apr 2015 Posts: 5336 Followers: 84 Kudos [?]: 1092 [0], given: 4955 Re: At Didymus Corporation there are just two classes of employe [#permalink] 20 Sep 2018, 11:33 Expert's post it is cumbersome. You should always try to use the fastest approach. Regards _________________ GMAT Club Legend Joined: 07 Jun 2014 Posts: 4855 GRE 1: Q167 V156 WE: Business Development (Energy and Utilities) Followers: 98 Kudos [?]: 1715 [0], given: 397 Re: At Didymus Corporation there are just two classes of employe [#permalink] 20 Sep 2018, 15:53 Expert's post rajlal wrote: How can we take the algebraic approach? Assume a salary for Silver employees=x Now then salary of gold employees = x +$56,000.

Average salary of of comapny is = $$\frac{160 (x+56000)+ 120x}{160+120}$$

Difference between comapany average and silver =$$\frac{160 (x+56000)+ 120x}{160+120}-x$$=$$\frac{160 (x+56000)+ 120x -(160+120)x}{160+120}$$= $$\frac{160 (56000)}{160+120}=32000$$
_________________

Sandy
If you found this post useful, please let me know by pressing the Kudos Button

Try our free Online GRE Test

Senior Manager
Joined: 09 Nov 2018
Posts: 481
Followers: 0

Kudos [?]: 16 [0], given: 1

Re: At Didymus Corporation there are just two classes of employe [#permalink]  10 Jan 2019, 21:02
rajlal wrote:
At Didymus Corporation there are just two classes of employees: Silver and Gold. The average salary of Gold is $56000 higher than that of silver employees. If there are 120 silver employees and 160 gold employees then the average salary for the company is higher than the average salary for the silver? A) 8000 B) 15000 C) 25000 D) 32000 E) 36000 Please fix typo should be then the average salary for the company is how much higher than the average salary for the silver employees Senior Manager Joined: 09 Nov 2018 Posts: 481 Followers: 0 Kudos [?]: 16 [0], given: 1 Re: At Didymus Corporation there are just two classes of employe [#permalink] 10 Jan 2019, 21:21 MAGOOSH OFFICIAL SOLUTION wrote: We can use this if we pick a value for the average salary for the silver employees. It actually doesn’t matter what value we pick, because averages will fall in the same relative places regardless of whether all the individual values are slid up and down the number line. The easiest value by far to pick is zero. Let’s pretend that the silver folks make$0, and the gold folks make $56. (I divided dollars by 1000 for simplicity). Now, we also have to simplify the numbers of employees. We could reduce the number of employees as long as we preserve the relative ratio. silver : gold = 120:160 = 12:16 = 3:4 So everything would be the same if we just had 3 silver employees and 4 gold employees. OK, now find the sums. silver = 3*0 = 0 gold = 4*56 I am not even going to bother to multiply that out, because we know that the next step is to divide by 7, the total number of employees. total average = 4*56/7 = 4*8 = 32 The average salary is$32,000, which is $32,000 higher than the average for the silver employees. Answer = (C) Intern Joined: 22 Aug 2018 Posts: 26 Followers: 0 Kudos [?]: 4 [0], given: 4 Re: At Didymus Corporation there are just two classes of employe [#permalink] 12 Jan 2019, 04:03 AE wrote: rajlal wrote: At Didymus Corporation there are just two classes of employees: Silver and Gold. The average salary of Gold is$56000 higher than that of silver employees. If there are 120 silver employees and 160 gold employees then the average salary for the company is higher than the average salary for the silver?

A) 8000
B) 15000
C) 25000
D) 32000
E) 36000

should be then the average salary for the company is how much higher than the average salary for the silver employees

The question is correct from the source. If you have any problem I expect you to take it with Magoosh team and not bicker it with me.

Bye bye
Moderator
Joined: 18 Apr 2015
Posts: 5336
Followers: 84

Kudos [?]: 1092 [0], given: 4955

Re: At Didymus Corporation there are just two classes of employe [#permalink]  12 Jan 2019, 04:35
Expert's post
Guys no need to pick some wasteful dull fights.

Often the questions from NON-official resources have typos.

As well, those from OFFICIAL resources.

As such, it is just a question. Wed o have on the board countless questions more. Move on.

Thank you
_________________
Supreme Moderator
Joined: 01 Nov 2017
Posts: 302
Followers: 3

Kudos [?]: 84 [0], given: 1

Re: At Didymus Corporation there are just two classes of employe [#permalink]  12 Jan 2019, 06:27
Expert's post
rajlal wrote:
At Didymus Corporation there are just two classes of employees: Silver and Gold. The average salary of Gold is \$56000 higher than that of silver employees. If there are 120 silver employees and 160 gold employees then the average salary for the company is higher than the average salary for the silver BY ?

A) 8000
B) 15000
C) 25000
D) 32000
E) 36000

you can use weighted average method too...

........gold.............silver
average..x............x+56000...
weights... 160.............120..

so company'S AVERAGE = $$x+56000*\frac{120}{120+160}=x+56000*\frac{120}{280}=x+200*120=x+24000$$

difference in silver and company's average = (x+56000)-(x+24000)=x+56000-x-24000=32000
_________________

Some useful Theory.
1. Arithmetic and Geometric progressions : https://greprepclub.com/forum/progressions-arithmetic-geometric-and-harmonic-11574.html#p27048
2. Effect of Arithmetic Operations on fraction : https://greprepclub.com/forum/effects-of-arithmetic-operations-on-fractions-11573.html?sid=d570445335a783891cd4d48a17db9825
3. Remainders : https://greprepclub.com/forum/remainders-what-you-should-know-11524.html
4. Number properties : https://greprepclub.com/forum/number-property-all-you-require-11518.html
5. Absolute Modulus and Inequalities : https://greprepclub.com/forum/absolute-modulus-a-better-understanding-11281.html

Re: At Didymus Corporation there are just two classes of employe   [#permalink] 12 Jan 2019, 06:27
Display posts from previous: Sort by