Question

5 charts and 6pencil together cost rs54 whereas 7 charts and 8 pencils together cost ra 74 find the cost of one chart and that of one pencil ?​

Answer 1

Cost of 5 charts + 6 pencils = Rs 54...(i)

Cost of 7 charts + 8 pencils = Rs 74...(ii)

Since we need the value of at least one item, we multiply both sides of Eqn (i) with 7, and get —

(5 charts + 6 pencils)×7=Rs 54×7

=> 35 charts + 42 pencils = Rs 378...(iii)

Similarly, we multiply both sides of Eqn (ii) with 5, and get —

(7 charts + 8 pencils) ×5=Rs 74×5

=> 35 charts + 40 pencils = Rs 370...(iv)

Therefore, subtracting Eqn (iv) from Eqn (iii)—

35 charts + 42 pencils = Rs 378

(-) 35 charts + 40 pencils = Rs 370

=> 2 pencils = Rs 8

=> 1 pencil = Rs 4

Therefore, applying the value of 1 pencil in Eqn (i),

5 charts + (6×4) = Rs 54

=> 5 charts = Rs (54-24)

=> 5 charts = Rs 30

=> 1 chart = Rs 6

Ans) Values of 1 chart and 1 pencil are Rs 6 & Rs 4 respectively

Answer 2

Answer:

Step-by-step explanation:

Let cost of 1 chart = Rs. X

      cost of 1 pencil = Rs. Y

         5x + 6y = 54.   * 7

          7x + 8y = 74.   * 5

        35x + 42x = 378

        35x + 42x = 370

           -         -         -

                      -2.      -8

                 X = 8/2

                  X = 4

  Cost of 1 = 4 Rs

      24 + 5y = 54

               5y = 54 - 24

                 Y = 30/5

                  Y = 6

  Cost of 1 pencil = 6