Question 9: The number of people living on a remote island decreases by 9% every 10 years.
In 1950 there were 18000 living on the island.
Calculate how many less people will be living on the island in 2020.
Question 10: A car was bought for £20,000.
Its value depreciates by 31% each year for the first four years.
What is its values at the end of the four years?
Question 11: A tree is 80cm when planted.
Each year the height of the tree increases by 22%.
After how many complete years will the height of tree be at least 3m?
Question 12: The number of polar bears in a region is decreasing by 5% per year.
There are 3000 polar bears in the region in 2017.
What year will be the first year with less than 1000 polar bears in the
region?
Question 13: Michael has started working for a company on a salary of £15000.
Each year he will be given a 6% pay rise.
How many years will it take for Michael's salary to exceed £30000?
Question 14: The value of a car decreases by 7.2% each year.
When bought the car cost £6200.
How many years will it take the car to have a value less than £1000?
Question 15: A full water tank has sprung a leak.
4% of the water is lost every minute.
What percentage of water is left in the tank after twenty minutes?
Question 16: A fish tank, that is full of water, has sprung a leak.
12% of the water is lost every hour.
What percentage of the water is lost after three hours?