A certain meter records voltage between 0 and 10, inclusive

Question

A certain meter records voltage between 0 and 10 volts inclusive. If the average value of 3 recordings on the meter was 8 volts, what was the smallest possible recording in volts?

A. 2
B. 3
C. 4
D. 5
E. 6

BrentGMATPrepNow · Accepted Answer

Sum of values = (# of values)(mean) 
So,  sum of the 3 reading s = (3)( 8 ) =  24

To  MINIMIZE  one of the readings, we must  MAXIMIZE  the other two readings. 
The maximum reading is 10, so let two of the readings equal 10.

Since the sum of all 3 readings must be  24 , the last remaining reading (the SMALLEST reading) must equal 4

Answer: C

RELATED VIDEO FROM OUR COURSE
 https://www.youtube.com/watch?v=Y9f_0QJU1ug

BG · Answer

Hallo,
If the average of the three outcomes is 8 then ther sum of the measurments is 24. The least possible is when the other 2 are max or 10 volts, then the least is 24-20=4

ywilfred · Answer

Total voltage = 24

Cannot be 2 as that will result in 22 being split among two other readings. Assuming 1 reading is 10, there's still one reading that needs to be at 12 volts, which is impossible.

Cannot be 3 as well for the same reasoning. 

Smallest reading: 4V 

Ans C

gmatacer · Answer

if average of 3 is 8 so sum of 3 should be 24

3 recording can be from 0-10 inclusive

to find one smallest other two should be highest

so, lets assume three var are a,b,c

say a is smallest and give b and c greatest readings say 10 and 10

so a has to be 4

SunShine · Answer

C.

3 reading, 3*8 =24, 
 max can be 10, so 10+10 =20, 24-20 =4

GyanOne · Answer

If the average of three readings was 8, then the sum of the three readings would be 8*3 = 24.

Now, to get the smallest possible value for one reading, make the other two readings as large as possible (10). Therefore the smallest possible reading = 24 - 10 - 10 = 4

Option (C)

sashiim20 · Answer

Average of 3 readings was 8 Therefore Sum of 3 readings = 8 * 3 = 24 Meter records voltage between 0 and 10 , inclusive. 2 Highest possible reading would be = 10 + 10 = 20 Therefore Smallest possible reading would be = 24 -20 = 4 Answer (C)... _________________ Please Press "+1 Kudos" to appreciate.

Bismarck · Answer

OA:C

Let the three reading be  x,y  and  z .

According to the question

8=\frac{x+y+z}{3}

x+y+z=24

For finding the smallest possible reading, the other two should be maximum possible reading.

x+10+10=24

x=24-20=4

ScottTargetTestPrep · Answer

To make one number as small as possible, the other two numbers must be as large as possible. Thus, we will let the two greatest voltage readings be 10, and he lowest reading be n and create the equation for the average of the 3 readings:

(n + 10 + 10)/3 = 8

n + 20 = 24

n = 4

Answer: C

Jitesh8 · Answer

Super easy

2*10 will give 20 and average is 8 so total will be 24
24-20=4

Opt C

Posted from my mobile device

bumpbot · Answer

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.

A certain meter records voltage between 0 and 10, inclusive

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Problem Solving (PS) Questions

A certain meter records voltage between 0 and 10, inclusive

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards