Approximately how many revolutions will be made by a car tire with a 12-inch diameter if the car travels 1 mile?	Pick:  A) 1,205  B) 1,800  C) 1,356  D) 1,672  E) 1,440
Diameter of car tire = 12 inches   Radius of car tire = 6 inches = 6*2.54= 
<gadget id="calculator">6*2.54</gadget>
<output>15.24</output>
15.24 cm   Circumference of the car tire= 2*pi * 15.24 = 2 *3.14 *15.24= 95.71 cm   Distance traveled by car =1 mile = 1 *1.6= 
<gadget id="calculator">1 *1.6</gadget>
<output>1.6</output>
1.6 km= 1600 m = 1.6 * 10^5 cm   Number of revolutions =Distance traveled / Circumference of tire = 1.6 * 10^5 / 95.71 = 1671.72   Since the answer choices are far apart we should use estimation in this question .   Ideally ,in the GMAT the conversion between units would be provided .   Answer 1,672
<result>D</result>
Approximately how many revolutions will be made by a car tire with a 12-inch diameter if the car travels 1 mile?