Robin's bike has wheels that are 25 inches in diameter. After the front wheel picks up a tack, Robin rolls another 123 feet and stops. How far above the ground is the tack?

Question

mathstudent55 · Answer

How many revolutions does the wheel make in 123 ft?

anonymous · Answer

1476/25pi

gorv · Answer

first find how much he cover in one revolution ....

mathstudent55 · Answer

Good. 
That number is approx. 18.8 revolutions. 
The wheel picked up the tack on the part of the tire that was touching the ground. 
18.8 revolutions later, the car stopped.

mathstudent55 · Answer

Since after 18 complete revolutions, the same part of the tire was touching the ground, all you need to be concerned with is the extra 0.8 revolution the wheel rotated until the car stopped.

mathstudent55 · Answer

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