Summer is Coming! Join the Game of Timers Competition to Win Epic Prizes. Registration is Open. Game starts Mon July 1st.

 It is currently 17 Jul 2019, 03:45

### 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

# A gear 50 inches in diameter turns a smaller gear 30 inches in diamet

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 56268
A gear 50 inches in diameter turns a smaller gear 30 inches in diamet  [#permalink]

### Show Tags

26 Feb 2018, 23:22
00:00

Difficulty:

25% (medium)

Question Stats:

79% (01:18) correct 21% (01:15) wrong based on 48 sessions

### HideShow timer Statistics

A gear 50 inches in diameter turns a smaller gear 30 inches in diameter. If the larger gear makes 15 revolutions, how many revolutions does the smaller gear make in that time?

(A) 9

(B) 12

(C) 20

(D) 25

(E) 30

_________________
Senior PS Moderator
Joined: 26 Feb 2016
Posts: 3360
Location: India
GPA: 3.12
A gear 50 inches in diameter turns a smaller gear 30 inches in diamet  [#permalink]

### Show Tags

26 Feb 2018, 23:36
1
Bunuel wrote:
A gear 50 inches in diameter turns a smaller gear 30 inches in diameter. If the larger gear makes 15 revolutions, how many revolutions does the smaller gear make in that time?

(A) 9

(B) 12

(C) 20

(D) 25

(E) 30

If the gear with diameter 50 inches makes 15 revolutions,

then the smaller gear(diameter: 30 inches) makes $$\frac{50}{30} * 15 = 25$$ revolutions

Therefore, the smaller gear will make 25 revolutions n the same time(Option D)
_________________
You've got what it takes, but it will take everything you've got
Manager
Joined: 23 Sep 2016
Posts: 236
A gear 50 inches in diameter turns a smaller gear 30 inches in diamet  [#permalink]

### Show Tags

27 Feb 2018, 22:53
2
Bunuel wrote:
A gear 50 inches in diameter turns a smaller gear 30 inches in diameter. If the larger gear makes 15 revolutions, how many revolutions does the smaller gear make in that time?

(A) 9

(B) 12

(C) 20

(D) 25

(E) 30

IMO D circumference of circle is 2pie r and we have diameter than pie d
now we will find total distance covered in 15 revolution
so 15*50pie is total distance covered now we need to divide it by 30pie circumference of smaller circle as we need to find revolutions
15*50 pie/30pie= 25
If you like my explanation then please give me KUDOS
A gear 50 inches in diameter turns a smaller gear 30 inches in diamet   [#permalink] 27 Feb 2018, 22:53
Display posts from previous: Sort by