Question

The Pony Express was a mail delivery system in the Old West that used a series of men on horseback to deliver mail from St. Joseph, MO to Sacramento, CA along a trail that was 2000 miles long. True or false: If each rider traveled 100 miles, got a fresh horse every 10 miles, and maintained an average speed of 10 mi/hr, it took 150 horses for each delivery.

True
False

Answer 1

Answer:

False

Explanation:

We have a distance of 2000 miles if each rider traveled 100 miles we need:

$2000\,\,miles\,\dfrac{1\,\,rider}{100\,\,miles}=20\,rider$

Then we need 20 riders now each rider got a fresh horse every 10 miles then:

$100\,\,miles\,\dfrac{1\,\,fresh\,\, horse}{10\,\,miles}=10\,fresh\,\,horse$

Finally multiplying by the 20 riders:

$\dfrac{10\,\,horses}{1\,\,rider}20\,rider=200\,\,horses$

Then we need a total of 200 horses.