question_answer

The cost of a notebook is Rs. 10. Draw a graph after making a table showing cost of 2, 3, 4... notebooks. Use it to find

(a) the cost of 7 notebooks.

(b) the number of notebooks that can be purchased for Rs. 50.

Answer:

Let x: number of notebooks

y: cost of a notebook

x 1 2 3 4 5 6 7 8 y 10 20 30 40 50 60 70 80

(a) The cost of 7 notebooks is equal to the coordinate of the point (7, 70), i.e. cost of 7 notebooks = Rs. 70

(b) The number of notebooks that can be purchased for Rs. 50 is equal to the abscissa of the point (5, 50).

Hence, 5 notebooks can be purchased for Rs. 50.