A house is bought for £150,000 at the start of 2005. For 3 years it loses 10% of its original value per year. After this time it loses 10% per year. What was its value at the end of 2011/start of 2012?

Original value = 150,000  10% original value =15,000  After 3 years year is 2008, house value = 150,000 - 3*(15,000) = 105,000Until start of 2012 from start of 2008, so 4 years of compound intrest.  New value of house = 105,000 * (0.90)^4  = £68890.5