instructions.md

In this exercise you'll be writing code to analyze the production of an assembly line in a car factory. The assembly line's speed can range from 0 (off) to 10 (maximum).

At its slowest speed (1), 221 cars are produced each hour. The production increases linearly with the speed. So with the speed set to 4, it should produce 4 * 221 = 884 cars per hour. However, higher speeds increase the likelihood that faulty cars are produced, which then have to be discarded. The following table shows how speed influences the success rate:

• 1 to 4: 100% success rate.
• 5 to 8: 90% success rate.
• 9: 80% success rate.
• 10: 77% success rate.

You have two tasks.

1. Calculate the production rate per hour

Implement the AssemblyLine.production_rate_per_hour method to calculate the assembly line's production rate per hour, taking into account its success rate:

AssemblyLine.production_rate_per_hour(6)
#=> 1193.4

Note that the value returned is an instance of Float.

2. Calculate the number of working items produced per minute

Implement the AssemblyLine.working_items_per_minute method to calculate how many working cars are produced per minute:

AssemblyLine.working_items_per_minute(6)
#=> 19

Note that the value returned is an instance of Integer.