Question

Alice's book has 200 pages. Alice has read 75% of the pages in her book. Nina has read the same number of pages but only 50% of the pages in her book. How many pages are in Nina's book?

Answer 1

Alice has read 0.75*200 = 150 pages. The number of pages in Nina's book is
.. 150/0.50 = 300

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That is, 0.50*300 = 150, the number of pages Nina has read.