Question

18 Notebooks and 32 pens together cost Rs. 642, while 32 notebooks and 18 pencils together

cost Rs. 908. Find the cost of each notebook.​

Answer 1

Step-by-step explanation:

Hope it will help you ........

Answer 2

Answer:

cost of 1 notebook = rs 25

Step-by-step explanation:

let cost of 1 notebook = a

and cost of pen = b

given,

18a + 32b = 642

=> 2(9a+16b) = 642

=> 9a+16b = 642/2 = 321 ----(1)

also given,

32a + 18b = 908

=> 2(16a+9b) = 908

=> 16a+9b = 908/2 = 454 ----(2)

let's solve these equations by elimination method.

equation (1) × 16 : 144a+256b = 5136

equation (2) × 9 : 144a+81b = 4086

- - -

----------------------------------------------------

=> 175b = 1050

=> b = 1050/175 = 6

putting value of b in (1),

9a+16b = 321

=> 9a + 16×6 = 321

=> 9a + 96 = 321

=> 9a = 321 - 96 = 225

=> a = 225/9 = 25