Question

Deepak bought 3 notebooks and 2 pens for Rs. 80. His friend Ram  said that price of each notebook could be Rs. 25. Then three notebooks  would cost Rs.75, the two pens would cost Rs.5 and each pen could be for Rs. 2.50. Another friend Ajay felt that Rs. 2.50 for one pen was too  little. It should be at least Rs. 16. Then the price of each notebook would  also be Rs.16.Lohith also bought the same types of notebooks and pens as

Aditya. He paid 110 for 4 notebooks and 3 pens. Later, Deepak

guess the cost of one pen is Rs. 10 and Lohith guess the cost of one

notebook is Rs. 30.

(i) Form the pair of linear equations in two variables from this

situation by takingcost of one notebook as Rs. x and cost of one

pen as Rs. y.

(a) 3x+2y=80 and 4x+3y=110 (b) 2x+3y=80 and 3x+4y=110

(c) x+y=80 and x+y=110 (d) 3x+2y=110 and 4x+3y=80

(ii) Which is the solution satisfying both the equations formed in (i)?

(a) x=10, y=20 (b) x=20,y=10 (c) =x15,y=15 (d) none of these

fast plz​

Answer 1

Answer:

3 Pen +4 Notebook =110 rupees

Multiply by 5,

15 Pen +20 Notebook =550 rupees

7 Pen +5 Notebooks =170 rupees

Multiply by 4,

28 Pen +20 Notebook =680 rupees

15 Pen +20 Notebook =550 rupees

Equating and solving for Pen,

Cancelling notebook,

13 Pen =130 Hence,

Pen =10 rupees

Substituting,

3(10)+4 Notebook =110

4 Notebook =110−30 Hence,

Notebook =20 rupees

Step-by-step explanation:

hope this helps you ❤️