An oil company bores a hole 100m deep. Estimate the cost of boring if the cost is £40 for the first metre with an increase in cost of £5 a metre for each succeeding metre. The value of a lathe...

• An oil company bores a hole 100m deep. Estimate the cost of boring if the cost

         is £40 for the first metre with an increase in cost of £5 a metre for each

         succeeding metre.

• The value of a lathe originally valued at £5,000 depreciates 15% per annum.

          Calculate its value after 5 years. The machine is sold when it’s value is less

          then £500. After how many years is the lathe sold?