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 Your Progress

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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

Want to score 90 percentile or higher on GMAT CR? Attend this free webinar to learn how to pre-think assumptions and solve the most challenging questions in less than 2 minutes.

Want to solve 700+ level Algebra questions within 2 minutes? Attend this free webinar to learn how to master the most challenging Inequalities and Absolute Values questions in GMAT

During a trip that they took together, Carmen, Juan, Maria, a
[#permalink]

Show Tags

21 Jun 2018, 09:07

2

Top Contributor

4

00:00

A

B

C

D

E

Difficulty:

5% (low)

Question Stats:

95% (00:59) correct 5% (01:10) wrong based on 1249 sessions

HideShow timer Statistics

During a trip that they took together, Carmen, Juan, Maria, and Rafael drove an average (arithmetic mean) of 80 miles each. Carmen drove 72 miles, Juan drove 78 miles, and Maria drove 83 miles. How many miles did Rafael drive?

During a trip that they took together, Carmen, Juan, Maria, a
[#permalink]

Show Tags

21 Jun 2018, 18:33

Top Contributor

Bunuel wrote:

During a trip that they took together, Carmen, Juan, Maria, and Rafael drove an average (arithmetic mean) of 80 miles each. Carmen drove 72 miles, Juan drove 78 miles, and Maria drove 83 miles. How many miles did Rafael drive?

Re: During a trip that they took together, Carmen, Juan, Maria, a
[#permalink]

Show Tags

21 Jun 2018, 19:00

Bunuel wrote:

During a trip that they took together, Carmen, Juan, Maria, and Rafael drove an average (arithmetic mean) of 80 miles each. Carmen drove 72 miles, Juan drove 78 miles, and Maria drove 83 miles. How many miles did Rafael drive?

During a trip that they took together, Carmen, Juan, Maria, a
[#permalink]

Show Tags

21 Jun 2018, 19:02

4

During a trip that they took together, Carmen, Juan, Maria, and Rafael drove an average (arithmetic mean) of 80 miles each. Carmen drove 72 miles, Juan drove 78 miles, and Maria drove 83 miles. How many miles did Rafael drive?

Re: During a trip that they took together, Carmen, Juan, Maria, a
[#permalink]

Show Tags

23 Jul 2018, 18:41

1

Bunuel wrote:

During a trip that they took together, Carmen, Juan, Maria, and Rafael drove an average (arithmetic mean) of 80 miles each. Carmen drove 72 miles, Juan drove 78 miles, and Maria drove 83 miles. How many miles did Rafael drive?

A. 80

B. 82

C. 85

D. 87

E. 89

We can create the equation:

(72 + 78 + 83 + x)/4 = 80

233 + x = 320

x = 87

Alternate Solution:

Carmen drove 8 miles under the average, Juan drove 2 miles under the average and Maria drove 3 miles above the average. If we add these up, we get -8 + (-2) + 3 = -7; which means we are 7 miles under the average. Therefore, Rafael must drive 7 miles over the average to keep the average at 80 miles. Thus, Rafael drove 80 + 7 = 87 miles.

Re: During a trip that they took together, Carmen, Juan, Maria, a
[#permalink]

Show Tags

21 Apr 2019, 04:17

Arithmetic mean for 4 people was 80, so we multiply 80*4=320, and 320 is the sum of results for 4 people. now we subtract 320-(72+78+83)=87
_________________

Re: During a trip that they took together, Carmen, Juan, Maria, a
[#permalink]

Show Tags

21 Apr 2019, 08:19

[quote="Bunuel"]During a trip that they took together, Carmen, Juan, Maria, and Rafael drove an average (arithmetic mean) of 80 miles each. Carmen drove 72 miles, Juan drove 78 miles, and Maria drove 83 miles. How many miles did Rafael drive?

A. 80

B. 82

C. 85

D. 87

E. 89

Hi,

According to stem, total miles driven: 80*4=320 miles

Now, subtract the miles driven of the other drivers to find the miles driven for Rafael

Re: During a trip that they took together, Carmen, Juan, Maria, a
[#permalink]

Show Tags

21 Apr 2019, 08:23

[quote="Bunuel"]During a trip that they took together, Carmen, Juan, Maria, and Rafael drove an average (arithmetic mean) of 80 miles each. Carmen drove 72 miles, Juan drove 78 miles, and Maria drove 83 miles. How many miles did Rafael drive?

A. 80

B. 82

C. 85

D. 87

E. 89

Total miles driven = 80*4 people = 320 miles Miles driven by Carmen, Juan and Maria = 72+78+83 = 233 miles Miles driven by Rafael = 320 - 233 = 87 miles Hence, OA: D

Re: During a trip that they took together, Carmen, Juan, Maria, a
[#permalink]

Show Tags

10 May 2019, 12:04

Bunuel wrote:

During a trip that they took together, Carmen, Juan, Maria, and Rafael drove an average (arithmetic mean) of 80 miles each. Carmen drove 72 miles, Juan drove 78 miles, and Maria drove 83 miles. How many miles did Rafael drive?