The coach of a cricket team buys 7 bats and 6 balls for Rs.3800. Later, she buys 3 bats and 5 balls for Rs.1750. Find the cost of each bat and each ball

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 3. Form the pair of linear equations for the following problems and find their solution by substitution    method

(iii) The coach of a cricket team buys 7 bats and 6 balls for Rs.3800. Later, she buys 3 bats and 5 balls for  Rs.1750. Find the cost of each bat and each ball.

Solution:

 let be one bat cost=Rs.x

 let be one ball cost=Rs.y

 7 bats and 6 balls cost-3800

     7x+6Y=3800------(1)

 3 bats and 5 balls cost = 1750

     3x+5y=1750-------(2)

  By solving equation (1)

     7x+6y=3800

     6y=3800-7x

     Y=(3800-7x)/6--------(3)

   Substitute y=(3800-7x)/6 in equation (2)

    3x+5y=1750

    3x/1+5(3800-7x)/6=1750 

    18x+19000-35x/6=1750

    19000-10500=17x

    x=8500/17=500

    X=500

Substitute x=500 in equation (3)

    y=(3800-7x)/6=3800-7(500)/6

     =3800-3500/6=300/6=50

    y=50

   x=500, y=50


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