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Eli read four more biographies than historical fiction book during the semester. He also read two fewer mysteries than historical fiction books. If he read a total of eleven books during the semester how many of each type of books did he read?

User Haochen Wu
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2 Answers

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Answer:the number of biographies books that Eli read is 7

the number of historical fiction books that Eli read is 3

the number of mysteries books that Eli read is 1

Explanation:

Let x represent the number of biographies books that Eli read.

Let y represent the number of historical fiction books that Eli read.

Let z represent the number of mysteries books that Eli read.

Eli read four more biographies than historical fiction book during the semester. This means that

x = y + 4

He also read two fewer mysteries books than historical fiction books. This means that

z = y - 2

If he read a total of eleven books during the semester, it means that

x + y + z = 11 - - - - - - - - - - - - 1

Substituting x = y + 4 and z = y - 2 into equation 1, it becomes

y + 4 + y + y - 2 = 11

3y + 2 = 11

3y = 11 - 2 = 9

y = 9/3 = 3

z = y - 2 = 3 - 2 = 1

x = y + 4 = 3 + 4 = 7

User Elbbard
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3 votes

Answer: Eli read 3 historical fiction books , 7 biographies and 1 mystery book.

Explanation:

Let x be the number of historical fiction books Eli read.

Then, Number of biographies he read = x+4

Number of mysteries he read = x-2

If he read a total of eleven books during the semester , then we have the following equation :


x+x+4+x-2=11


\\\\\Rightarrow\ 3x+2=11


\\\\\Rightarrow\ 3x=9 (Subtract 2 from both sides )


x=3 (Divide both sides by 3)

Therefore , Number of historical fiction books Eli read = 3

Number of biographies he read = 3+4=7

Number of mysteries he read =3-2=1

Hence, Eli read 3 historical fiction books , 7 biographies and 1 mystery book.

User Jalanda
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