A tractor has a front wheel diameter of h cm and rear wheel diameter

Question

A tractor has a front wheel diameter of h cm and rear wheel diameter of k cm. The front wheel covers a distance of m meters in 1000 revolutions. How many revolutions does the rear wheel make in covering m meters?

A. 1000h/k
B. 1000k - h
C. 1000hk
D. 1000h - k
E. 1000k/h

A. 1000h/k 
B. 1000k - h 
C. 1000hk
D. 1000h - k
E. 1000k/h

GMATinsight · Answer

Since both the wheels belong to the same vehicle hence at any time the distance travelled by both the wheels should be equal

i.e. Distance of wheel 1 = Distance pf wheel 2

i.e. Circumference*Number of revolutions of wheel 1 = Circumference*Number of revolutions of wheel 2

i.e. Diameter*Number of revolutions of wheel 1 = Diameter*Number of revolutions of wheel 2

i.e. h*1000 = k*Revolutions

i.e. Revolutions of wheel 2 = h*1000/k

Answer: option A

chetan2u · Answer

The revolution would depend on the circumference ..
Let the dia h be twice of k.......h=2k
Since role of dia is a linear function in circumference, that is  \pi*dia 
If h takes 1000 revolution to cover m meter, k will take 2000 as k is half of h..
Look for choice that gives 2000 by substituting h =2k
Only A and E will remove variables..
A. 1000h/k....1000*2k/k=2000....... YES
E. 1000k/h...... 1000*k/2k=500......No

Ans A

ScottTargetTestPrep · Answer

The circumference of the front wheel is hπ and that of the rear wheel is kπ. The number of revolutions of a wheel to cover a distance is equal to the distance divided by the circumference of the wheel; thus, we see that m/(hπ) = 1000 or m = 1000hπ. Therefore, the number of revolution the rear wheel makes is

m/(kπ) = 1000hπ/kπ = 1000h/k

Answer: A

SaquibHGMATWhiz · Answer

Solution:

Front Wheel:    Circumference  =2\pi 	imes \frac{h}{2}=\pi h    No. of revolutions  =1000     Distance = Circumference * No. of resolution    Or  m=\pi h	imes 1000......(i)

Rear Wheel:    Circumference  =2\pi 	imes \frac{k}{2}=\pi k    Distance  =m     Distance = Circumference * No. of resolution    Therefore,  	ext{No. of revolution}   = \frac{Distance}{Circumference} = \frac{m}{\pi k}=\frac{\pi h	imes 1000}{\pi k}=\frac{1000h}{k}

Hence the right answer is    Option A

ThatDudeKnows · Answer

We are talking about proportions. 
Why would we ever subtract either h or k at the end? Eliminate B and D.
C can't be right or we would just end up with a bigger and bigger number regardless of whether we increase the size of h or increase the size of k.
We are down to A and E. If h is big and k is small, the number of revolutions for the rear wheel will be larger than the number of revolutions for the front wheel. Answer choice A is (1000*big)/small, which is bigger than 1000, so that could work. Answer choice E is (1000*small)/big, which is smaller than 1000, so we can eliminate E. 
Only one answer choice remains.
Answer choice A.

Quantitative REASONING.

A tractor has a front wheel diameter of h cm and rear wheel diameter

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A tractor has a front wheel diameter of h cm and rear wheel diameter

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