John has a job that requires him to travel 3 of every 4 weeks. He has an annual budget and can travel either by train or by plaine. The airline on which he typically flies has a frequent traveler programme that reduces the cost of his tickets according to the number of milels he has flown in a given year. When he reaches 25000 kilometres, the airline will reduce the price of ticket by 25 percent for the remainder of the year. When he reaches 50000 kilometres, the airline will reduce the price by 50 percent for the remainder of the year. Graphically illustrate john's budget line, with train kilometres on the vertical axis and plane kilometres on the horizontal axis.

To graphically illustrate John's budget line, we need to plot the combinations of train and plane kilometers that he can afford based on his annual budget.

Let's assume John's annual budget is represented by a straight line on the graph. The vertical axis will represent train kilometers, and the horizontal axis will represent plane kilometers.

1. Start by plotting two points on the graph to define the budget line:
- When John has not yet reached 25,000 kilometers on the plane, mark a point on the plane axis where the budget line intersects.
- When John has reached 25,000 kilometers on the plane, mark a point on the plane axis where the budget line intersects.

2. Connect these two points with a straight line. This line represents John's budget line.

3. Now, let's consider how John's budget line changes when he reaches 25,000 kilometers on the plane and when he reaches 50,000 kilometers.
- Once John reaches 25,000 kilometers on the plane, the airline will reduce the price of his tickets by 25% for the remainder of the year. This means he can afford to travel more plane kilometers within his budget. Therefore, his budget line would shift outward or become flatter to reflect this.
- Once John reaches 50,000 kilometers on the plane, the airline will further reduce the price of his tickets by 50% for the remainder of the year. This means he can afford to travel even more plane kilometers within his budget. Therefore, his budget line would shift outward again or become flatter to reflect this.

By taking into account these changes, adjust the slope and position of John's budget line accordingly.

Remember that train kilometers are represented by the vertical axis, and plane kilometers are represented by the horizontal axis.