Question

Mohan purchased 3 pencil and 1 pen for Rs.10 and Sumit purchased 2pencil and 3 pen for Es 16 find the price of one pen and one pencil algebraically.

Answer 1

Answer:

∴ Cost of one pencil is Rs.2 and cost of one pen is Rs.4

Step-by-step explanation:

Let the cost of one pencil be X and cost of one pen be Y

Cost of 3 pencil + cost of 1 pen = 10

                                        3X + Y = 10

                                                 Y = 10 - 3X ------- ( i )

Also,

cost of 2 Pencil + cost of 3 Pen = 16

                                      2X + 3Y = 16

Putting value of Y from ( i )

                          2X + 3(10 - 3X) = 16

                             2X + 30 - 9X = 16

                                             -7X = -14

                                                X = 2

Putting value of X in ( i )

                                  Y = 10 - 3(2)

                                  Y = 10 - 6

                                  Y = 4

∴ Cost of one pencil is Rs.2 and cost of one pen is Rs.4