Tour package extendable on pro-rata basis. What does this mean ?

Question

Please illustrate with an example.

Answer 1

It means that if you want to be on a longer tour than the example they have provided, the cost will be incrementally more, based on the overall rate per day, for every day you are on it.

For example, if a week long tour costs $700 for a week, and you extend it to ten days, you would expect to pay $1000 ($700/7 x 10 = $1000)