A man, while driving on a highway at uniform speed, observes his car’s

Question

A man, while driving on a highway at uniform speed, observes his car’s odometer reading just turned to 18992 miles. What is the speed at which the man was driving?

(1) After 5 hours, the odometer reading of the car showed a five-digit palindrome as the total distance travelled (A palindrome is a number which reads the same forward as well as backward).

(2) After 2 hours, the man found that he had travelled less than 80 miles.

GMATinsight · Answer

Speed = \frac{Distance}{Time}

Question : Speed of car = ?

Statement 1 :After 5 hours, the odometer reading of the car showed a five-digit palindrome as the total distance travelled (A palindrome is a number which reads the same forward as well as backward) 
i.e. the odometer after 5 hours could be 19091 or 19191 or 19291 etc
Different distance possible in 5 hours leading to different speeds hence
NOT SUFFICIENT

Statement 2 :After 2 hours, the man found that he had travelled less than 80 miles. 
less than 80 miles will lead to multiple distances (79 or 78 or 78 miles etc) travelled in 2 hours hence
NOT SUFFICIENT

Combining the two statements

If odometer reading changes from 18992 to 19091
then total distance travelled = 19091 - 18992 = 99 miles 
i.e. speed = 99/5 = 19.8 miles/hours i.e. 39.6 miles in 2 hours

If odometer reading changes from 18992 to 19191
then total distance travelled = 19091 - 18992 = 199 miles 
i.e. speed = 99/5 = 39.8 miles/hours i.e. 79.6 miles in 2 hours

i.e. different speeds ate acceptable even now hence

SUFFICIENT

Answer: Option C

mohshu · Answer

GMATinsight  the answer shud be E..

Leo8 · Answer

A man, while driving on a highway at uniform speed, observes his car’s odometer reading just turned to 18992 miles. What is the speed at which the man was driving?

(1) After 5 hours, the odometer reading of the car showed a five-digit palindrome as the total distance travelled (A palindrome is a number which reads the same forward as well as backward).

(2) After 2 hours, the man found that he had travelled less than 80 miles.

Clearly statement 1 & 2 are not sufficient individually.

from statement 2 we know that the maximum distance the man can cover must be less than 200 miles in 5 hours

Maximum reading on odometer = 18992 + 200 miles = 19292 miles
we know the minimum reading is 18992 and maximum 19292

from statement   we know that the reading after 5 hours is a palindromic one so we can have
19091 or 19191 or 19291

three possible values - hence E

Lowkya · Answer

Hi,

Your approach is right but there is a small calculation mistake.
 Maximum reading on odometer = 18992 + 200 miles = 19292 miles 
It should be  19192. 
So, possible palindromes are 19091 and 19191.

Thanks.

chetan2u · Answer

A man, while driving on a highway at uniform speed, observes his car’s odometer reading just turned to 18992 miles. What is the speed at which the man was driving?

(1) After 5 hours, the odometer reading of the car showed a five-digit palindrome as the total distance travelled (A palindrome is a number which reads the same forward as well as backward).
 No upper limit , it can be anything....
19091, 22222 
Insufficient

(2) After 2 hours, the man found that he had travelled less than 80 miles.
Just tells us that the speed is less than 40mph
So insufficient

Combined
Speed<40mph, so could have travelled <200 in 5 hours..
Or <18992+200=19192...
Palindromes between 18992 and 19192 are 19091 and 19191
So two possible answers
Insufficient

E

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A man, while driving on a highway at uniform speed, observes his car’s

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