Question

8.Shivi gave a note of ₹2,000 for a pair of jeans worth ₹500. She was returned 11 notes in denominations of ₹200 and ₹100. Which pair of equations can be used to find the number of ₹200 notes, x, and the number of ₹100 notes y? How many notes of ₹200 did she get?

1. =+11 200+100=2000;4
2. +=11 100+200y=2000;10
3. +=11 200+100y=5000;4
4. +=11 200+100=1500;8

Answer 1

Given:

The cost of jeans = ₹500

The amount paid by Shivi = ₹ 2000

Number of notes of ₹200 = x

Number of notes of ₹100 = y

Total number of notes returned = 11  

To Find:

The equation which represents the number of notes returned to Shivi

Solution

• For finding the solution to this question, we will go through the following steps:

Step 1: Find the balance owed to Shivi.

• The cost of the jeans = ₹500
• Amount paid by Shivi = ₹2000

∴ The amount received back by Shivi = ₹2000 - ₹500

                                                        = ₹1500

Step 2: Form an equation for the number of notes returned.

• Number of notes of ₹200 = x
• Number of notes of ₹100 = y
• Total number of notes = x + y

• Value of x notes of ₹200 = 200x
• Value of y notes of ₹100 = 100y

∴ Total number of notes returned = 200x + 100y

Step 3: Equate the number of notes with the calculated value.

• From Step 1, we know that the total amount returned = ₹1500
• From Step 2, we know that the total value of notes returned can be written as:

                          200x + 100y = 1500                    (1)

Step 4: Equate the number of notes returned

• It is given that the total number of notes returned = 11

• From Step 2 we know that the expression for the total number of notes returned is:

                          x + y = 11                                  (2)

Step 5: Find the value of x and y

• From steps (3) and (4), we have two equations representing the number and value of notes returned.

• Equating values from (1) and (2):

                              x + y = 11

                           ⇒ y = 11 -x

Substituting value of y in (1)

                                ⇒200x + 100(11 - x) = 1500

                               ⇒200x + 1100 - 100x =1500

                               ⇒ 100x = 400

                               ⇒ x = 4

Therefore, 4 notes of ₹200 were returned.

Hence, equations used for finding the number of ₹200 notes are:

x + y = 11  and 200x + 100y = 1500  

Shivi got 4 notes of ₹200.

 

Answer 2

Step-by-step explanation:

Plzzz....understand it in a proper way......