Question

When a certain tree was first planted, it was 4 feet tall, and the height of the tree increased by a constant amount each year for the next 6 years. at the end of the 6th year, the tree was \frac{1}{5} taller than it was at the end of the 4th year. by how many feet did the height of the tree increase each year?

Answer 1

Let the height increase each year be x. If the initial height was 4 ft, then its height after 6 years would be 4 + 6x. This is 1/5 taller than its initial height, so
4 + 6x = 4(1 + 1/5)6x = 4/5x = 2/15 ft per year