GMAT Prep Practice Test

[Saurabh]

When a certain tree was planted it was 4 ft 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 1/5 taller then it was at the end of 4th year. By how many feet did the height of the tree increased each year?

1) 3/10
2) 2/5
3) 1/2
4) 2/3
5) 6/5

I really had no idea stacey how to go about solving this question the only thing I could try was plug in numbers to check I would really like to know how to answer this question

[Saurabh]

The wordings of this question was very confusing once you understand what it means equation is very easy.

(4+4x)/5 + 4+4x=4+6x
4+4x=10x
therefore x=2/3