Question 3

The cost of 2 kg of apples and 1kg of grapes on a day was found to be ` 160. After a month, the cost of 4 kg of apples and 2 kg of grapes is ` 300. Represent the situation algebraically and geometrically.

Answer

Let the cost of one kg apple be x ₨ and 1 kg grapes be y ₨.

According to first condition,

2x + y = 160 ₨ …………..(1)

According to second condition,

4x + 2y = 300

2x + y = 150 ……………….(2)

** Graphical Representation**

Table for equation (1), 2x + y = 160

Table value of x and y

x: |
40 |
60 |
80 |

y: |
60 |
40 |
0 |

Table for equation (2), 2x + y = 150

Table value of x and y

x: |
40 |
60 |
20 |

y: |
70 |
30 |
110 |

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- NCERT Chapter