Question

3. In 1862, two companies were given the rights to build a railroad from Omaha, Nebraska to

Sacramento, California. The Central Pacific Company began from Sacramento in 1863 and averaged
8.75 miles of track per month. Twenty-four months later the Union Pacific Company started from
Omaha and averaged 20 miles of track per month. The two railroad companies finally met in
Promontory, Utah, completing the 1,590 mile rail line. How long did this project take? How many
miles of track did each company build?​

Answer 1

Explanation:

Interesting bit of trivia if true.

The central Pacific Railway had a 24 month head start. Each month let them go 8.75 miles, so the total distance the rail went was 24*8;75 = 210 miles. They built this before the Union Pacific had done 1 mile of track.

So now when the Union Pacific started building, there remained 1590 - 210 miles of track to be laid. 1590 - 210 = 1380 miles of track.

The rest is pretty straight forward. Between the two rail companies, they built 28.75 miles of track a month.

Therefore the number of months = 1380/28.75 = 48 months.

The project took (in total) 48 + 24 = 72 months to build.

The Union Pacific built 48 * 20 = 960 miles of rail

The Central Pacific built 72 * 8.75 = 630 miles of rail

Total distance = 1590 miles which is the stated total.

Answers

Total Time = 72 months.

Union Pacific distance built = 960 miles

Central Pacific distance built = 630 miles