You will be given a definition of a task first, then an example. Follow the example to solve a new instance of the task.
In this task, you're given an article and an answer. Your task is to generate the question for the answer based on the given article.

Article: There are a lot of public libraries in Britain. These libraries have more than one hundred and fifteen million books, not including those libraries of public schools. Public libraries not only lend books, music records but also help children, patients in hospitals and others to get special play readings, film shows and so on. The first public libraries were founded in about the year 1850. Today's public libraries usually have a reading-room, a lending room and a reference room. The greatest and most famous library in Britain is that of the British Library in London. It was founded in 1973 and has over 10, 000, 000 books. It has nearly every magazine, newspaper and book published in Britain and other parts across the world.
Answer: 10,000,000 or less.
Solution: How many books are there in the British Library?
Why? In the Article, 10,000,000 is mentioned for the number of books available in the British Library, so this is a good question.

New input: Article: Mini Hoover Dam Tour ONLY $48 per person LIST PRICE $60 This tour begins with beautiful sights as you travel by coach through famous Las Vegas towards Boulder City, Nevada. As you leave Boulder City on your way to the famous Hoover Dam, you will see in the distance Lake Mead. Created by the Hoover Dam, it is one of the largest and most beautiful man-made lakes in America! When you arrive at Hoover Dam, you can visit the museum, watch a movie on the Dam's construction and see Oskar J.W. Hansen's famous sculptures on the Nevada side. Experience the excitement of this man-made wonder with great views that will create memories of a lifetime! Tour Highlights * Free hotel-to-hotel pick-up and drop-off * Coaches with windows for your viewing pleasure * Beautiful views of man-made Lake Mead * Experience the Hoover Dam from two states * Hoover Dam Discovery Tour * Time for souvenir shopping * Relax and enjoy our return journey by coach to Las Vegas
Answer: $24.
Solution:
How much will your parents save if they attend the Mini Hoover Dam Tour?