SOLUTION: Jonson and Mandy have some story books. If Jonson gives Mandy 5 books, they will have same number of books. If Mandy give Jonson 4 books, then the number of Jonson’s books is 3 t

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Jonson and Mandy have some story books. If Jonson gives Mandy 5 books, they will have same number of books. If Mandy give Jonson 4 books, then the number of Jonson’s books is 3 t      Log On


   



Question 1180701: Jonson and Mandy have some story books. If Jonson gives Mandy 5 books, they will have same number of books. If Mandy give Jonson 4 books, then the number of Jonson’s books is 3 times as many as Mandy’s. How many books does Jonson have?
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Jonson and Mandy have some story books.
If Jonson gives Mandy 5 books, they will have same number of books.
If Mandy give Jonson 4 books, then the number of Jonson’s books is 3 times as many as Mandy’s.
How many books does Jonson have?
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As you read the text, you write these equations


    J - 5 = M + 5      (1)    (from the first statement)

    J + 4 = 3*(M-4)    (2)    (from the second statement)



From first equation, express M = (J-5) - 5 = J - 10, and substitute it into the second equation

    J + 4 = 3*((J-10)-4).



Simplify and solve for J

    J + 4 = 3*(J-14)

    J + 4 = 3J - 42

    4 + 42 = 3J - J

      46   = 2J

       J   = 46/2 = 23.


ANSWER.  Jonson has 23 books.

Solved.