GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 16 Oct 2018, 22:36

### 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 John traveled 9 miles on his unicycle, what was his speed in miles

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 49916
If John traveled 9 miles on his unicycle, what was his speed in miles  [#permalink]

### Show Tags

18 Sep 2018, 21:59
00:00

Difficulty:

65% (hard)

Question Stats:

38% (01:01) correct 63% (07:39) wrong based on 56 sessions

### HideShow timer Statistics

If John traveled 9 miles on his unicycle, what was his speed in miles per hour?

(1) The unicycle has spokes that stretch the 23 inches from the center of the wheel to inner edge of the wheel.
(2) John pedals his unicycle at 19 revolutions per minute.

_________________
Director
Joined: 20 Feb 2015
Posts: 793
Concentration: Strategy, General Management
Re: If John traveled 9 miles on his unicycle, what was his speed in miles  [#permalink]

### Show Tags

26 Sep 2018, 23:16
Bunuel wrote:
If John traveled 9 miles on his unicycle, what was his speed in miles per hour?

(1) The unicycle has spokes that stretch the 23 inches from the center of the wheel to inner edge of the wheel.
(2) John pedals his unicycle at 19 revolutions per minute.

distance = 9 miles = n*2 $$\pi$$r (where n is the number of revolutions made by the unicycle)
speed = $$\frac{distance}{time}$$ =$$\frac{9}{time}$$ = ?

(1) The unicycle has spokes that stretch the 23 inches from the center of the wheel to inner edge of the wheel.

we are given radius = 23 inches
substituting the value back into the equation 9 miles = n*2 $$\pi$$r will give us n (number of revs)
time =?

not sufficient

(2) John pedals his unicycle at 19 revolutions per minute.
again we are not given time

not sufficient

E
Intern
Joined: 05 Sep 2016
Posts: 29
Location: India
Concentration: General Management, Operations
WE: Engineering (Energy and Utilities)
Re: If John traveled 9 miles on his unicycle, what was his speed in miles  [#permalink]

### Show Tags

27 Sep 2018, 01:20
Bunuel wrote:
If John traveled 9 miles on his unicycle, what was his speed in miles per hour?

(1) The unicycle has spokes that stretch the 23 inches from the center of the wheel to inner edge of the wheel.
(2) John pedals his unicycle at 19 revolutions per minute.

Fact:D=9 Miles, t=?, S=?
Question:Speed=Distance/Time=?

Condition1: The unicycle has spokes that stretch the 23 inches from the center of the wheel to inner edge of the wheel.
Please note it's given as inner edge. Not outer edge which would have given the exact circumference of wheel needed for calculation.
Not Sufficient.

Condition2: he moves at 19Revs/min= 1140 Revs/hr.
But not sufficient.

Condition (1)+(2): Circumference*revs/hr would give the distance travelled in 1 hour in inches/hr unit. Convert it to miles/in 1 hr. Divide 9 Miles/this figure to get the time.
BUT as stated in condition (1) Inner dia would not be accurate to solve this question, for this we need outer dia or circumference.

So, NOT SUFFICIENT.

ANS-E
Re: If John traveled 9 miles on his unicycle, what was his speed in miles &nbs [#permalink] 27 Sep 2018, 01:20
Display posts from previous: Sort by