Question:There are 10 books on the table. Two-fifths of them are reading books and three-tenths of them are math books. There is one fewer science book than math books and the rest are history books. How many history books are there?
Answer:Out of the 10 books, 10 x 2/5 = <<10*2/5=4>>4 are reading books.
While 10 x 3/10 = <<10*3/10=3>>3 are math books.
There are 3 - 1 = <<3-1=2>>2 science books.
So, the total number of reading, math, and science books is 4 + 3 + 2 = <<4+3+2=9>>9.
Thus, there is only 10 - 9 = <<10-9=1>>1 history book.
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