GMAT Question of the Day: Daily via email | Daily via Instagram New to GMAT Club? Watch this Video

 It is currently 05 Jul 2020, 22:56

### 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

# If b=8d - c, and a=d/3, what is the average of a,b,c and d?

Author Message
TAGS:

### Hide Tags

VP
Joined: 31 Oct 2013
Posts: 1491
Concentration: Accounting, Finance
GPA: 3.68
WE: Analyst (Accounting)
If b=8d - c, and a=d/3, what is the average of a,b,c and d?  [#permalink]

### Show Tags

01 Mar 2019, 09:05
1
1
2
00:00

Difficulty:

25% (medium)

Question Stats:

78% (01:55) correct 22% (01:59) wrong based on 55 sessions

### HideShow timer Statistics

If b=8d - c, and a=d/3, what is the average of a,b,c and d?

A) 4a
B) 7a
C) a/7
D) 4a + 7
E) a/7 + 5
Manager
Joined: 19 Jan 2019
Posts: 110
Re: If b=8d - c, and a=d/3, what is the average of a,b,c and d?  [#permalink]

### Show Tags

01 Mar 2019, 09:50
1
Assume the value of a to be 4.
4 = d/3 => d = 12
b = 8d - c => b = 96-c
b+c = 96
Average of a,b,c,d = (a+b+c+d)/4
(4+12+96)/4 = 28..

Substitute the value of a as 4 in answer choices, we get option b as 28..

Posted from my mobile device
Senior Manager
Joined: 15 Feb 2018
Posts: 453
Re: If b=8d - c, and a=d/3, what is the average of a,b,c and d?  [#permalink]

### Show Tags

01 Mar 2019, 19:42
1
Have each letter in terms of d
a=d/3
b=8d-c, b+c=8d
d=d

$$\frac{\frac{d}{3}+8d+d}{4}=\frac{\frac{28d}{3}}{4}=\frac{7d}{3}$$
The options are in terms of a, and we are told that a=d/3

$$\frac{7d}{3}=7a$$

B
Manager
Joined: 27 Nov 2018
Posts: 62
Re: If b=8d - c, and a=d/3, what is the average of a,b,c and d?  [#permalink]

### Show Tags

26 May 2019, 08:51
2
1
philipssonicare wrote:
Have each letter in terms of d
a=d/3
b=8d-c, b+c=8d
d=d

$$\frac{\frac{d}{3}+8d+d}{4}=\frac{\frac{28d}{3}}{4}=\frac{7d}{3}$$
The options are in terms of a, and we are told that a=d/3

$$\frac{7d}{3}=7a$$

B

Since answer is in multiples of a , it is better to convert each letter in terms of "a". No need to convert c in any form as it will get cancelled out while we write the average formula
d= 3a
b= 8d-c = 24a-c

(a+b+c+d)/4 = (a+24a-c+c+3a)/4 = 28a/4 = 7a
Non-Human User
Joined: 09 Sep 2013
Posts: 15382
Re: If b=8d - c, and a=d/3, what is the average of a,b,c and d?  [#permalink]

### Show Tags

28 May 2020, 05:56
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
Re: If b=8d - c, and a=d/3, what is the average of a,b,c and d?   [#permalink] 28 May 2020, 05:56