Question

prashant purchases 2 mobiles and 3 memory cards for just rs 6500.The cost of one mobile and one memory card is rs 2950 obtain a pair of linear equation

Answer 1

Given:

2 mobiles and 3 memory cards = Rs 6500

1 mobile and 1 memory card = Rs 2900

To FInd:

State a pair of linear equations

Solution:

Define x and y:

Let the cost of one mobile be x

Let the cost of one memory card be y

Define the linear equations

2 mobiles and 3 memory cards = Rs 6500

⇒ 2x + 3y = 6500

1 mobile and 1 memory card = Rs 2900

⇒ x + y = 2900

Solve x and y:

2x + 3y = 6500 ------------------  [ 1 ]

x + y = 2900      ------------------  [ 2 ]

[ 2 ] x 2 :

x + y = 2900

2x + 2y = 5800

[ 1 ] - [ 3 ]:

y = 6500 - 5800

y = 700

Sub y = 700 into [ 2 ]

x + 700 = 2900

x = 2900 - 700

x = 2200

Find the cost:

Mobile = x

Mobile = Rs 2200

Memory Card = y

Memory Card = Rs 700

Answer: The pair of linear equations are 2x + 3y = 6500 and x + y = 2900. Solving them, we found out that the mobile cost Rs 2200 and the memory card cost Rs 700.