Question

The total cost of 6 books and 7 pens is 79 rupees and the total cost of 7 books and 5 pens is 77 rupees. Find the cost of 1 book and 2 pens. ​

Answer 1

Answer:

The answer is 19.

Step-by-step explanation:

Given:-

• The total cost of 6 books and 7 pens is 79 rupees
• The total cost of 7 books and 5 pens is 77 rupees.

To find:-

• The cost of 1 book and 2 pens.

Solution: -

Let the cost of the book be x

And the cost of pen be y

Then the cost of 6 books n 7 pens is

6x + 7y = 79

And 7x + 6y = 77

Now let us add both equations

13x + 13y = 156

X + y = 12

Let us subtract both equations

-x + y = 2

Now let us add the equations so obtained then

X - x + y + y = 12 + 2

2y = 14

y = 7

Substitute in one equation then

X + 7 = 12

X = 5

So the cost of one book is 5

And one pen is 7

So the cost of 1 book and 2 pens is

X + 2y

= 5 + 2(7)

= 5 + 14

= 19

Hence, the cost of 1 book and 2 pens is 19. rupees.

Answer 2

Answer:

above answer was correct