Question

The price of 5 notebooks and 4 pens is 190 rupees. The price of 10 notebooks and 7 pens is 370 rupees. what is the price of a notebook. what is the price of a pen​

Answer 1

Answer:

Given total cost of 5 pens and 10 pencil = Rs 30

5 pens + 10 pencils = 30

pens + 2 pencils = 1

also given pen cost 3 more than a pencil

i.e, pen = 3 + pencil.

pen - pencil = 3

pens + 2 pencils = 6

_______________

-3 pencils = -3

pencils = 1

pen - 1 = 3

pen = 4

cost of pencils = 1 cost of pen = 4

Answer 2

Question:-

The price of 5 notebooks and 4 pens is 190 rupees. The price of 10 notebooks and 7 pens is 370 rupees. what is the price of a notebook. what is the price of a pen.

Solution:-

{ According to question }

• The price of 5 notebooks and 4 pens is 190 rupees.
• The price of 10 notebooks and 7 pens is 370 rupees.

Let, x be the cost of one notebook & y be the cost of one pen.

Now, according to question & assumption

We from an equation

—› 5x + 4y = 190 ........ ( 1 )

—› 10x + 7y = 370 ........ ( 2 )

{To find value of x ( notebook ) }

multiply eq. ( 1 ) by 2, we get,

—› 10x + 8y = 380 ....... ( 3 )

Now, subtract eq. ( 2 ) from eq. ( 3 )

10x + 8y = 380

- ( 10x + 7y = 370 )

____________________

y = 10

{To find value of y ( pen ) }

Now, put value of y in eq. ( 1 )

—› 5x + 4(10) = 190

—› 5x + 40 = 190

—› 5x = 190 - 40

—› 5x = 150

—› x = 150/5

—› x = 30

from value of x & y we know cost of one notebook is Rupees 30 & cost of one pen is Rupees 10 respectively.

{ Note :- To find cost of item [Notebooks/Pens]

—› Cost of Notebooks/Pens

= [Quantity of notebooks/pens]×[Cost of one notebook/pen] }

Hope it helps you.