Answer: The present age of Jim is 15 years.
Step-by-step explanation: Given that Jim's uncle is 4 times as old as his nephew Jim. In 10 years, Jim's uncle age will be 20 years more than twice Jim's age.
We are to find the present age of Jim.
Let x years and y years be the present ages of Jim and his uncle respectively.
Then, according to the given information, we have

and
![y+10=2(x+10)+20\\\\\Rightarrow y=2x+20+20-10\\\\\Rightarrow y=2x+30\\\\\Rightarrow 4x=2x+30~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~[\textup{Using equation (i)}]\\\\\Rightarrow 2x=30\\\\\Rightarrow x=15.](https://img.qammunity.org/2017/formulas/mathematics/high-school/7jyijp2us8ctklgs81x2pxd0eoceu69duv.png)
Thus, the present age of Jim is 15 years.