Distance

[Guest]

A statement from 1957. I made it into a problem:

A train's freight car wheels are 33 in. in diameter. 2 million cars were in service at that time. If the wheels were laid tread to tread, the distance would be x miles. Determine distance.

My calculations;

33 in. = .9166 = .92 ft.

A car has 8 wheels.

8 * 2000000 = 16000000 wheels.

16000000 / .92 = 17391304.34 ft.

17391304.34 / 5280 = 3293.80 = 3294 miles.

Where am I correct ?

[Guest]

33 inches÷12=2.75 feet

[Guest]

My error.

16000000 / 2.75 = 5818181.81 ft.

5818181.81 / 5280 = 1101.92 = 1102 miles.

Answer provided is more than 7.5 times that. How did they arrive with that answer ?

[Guest]

Please reply. Thanks.

[Guest]

Total length = Number of wheels × Diameter in feet = 16,000,000 × 2.75 = 44,000,000 feet

[Guest]

Ok, Thanks.

[GeradHum]

You correctly converted inches to feet and total wheels, but you should multiply wheels by wheel diameter to get total length, not divide. So total distance = 16,000,000 wheels × 0.92 ft = 14,720,000 ft, then convert to miles.

[Guest]

Thanks.