Q1 of 186 Page 3

Sudha went to market with her friends. They wanted to eat `gol - gappa' as well as `dahi - bhalla'. The number of plates of gol - gappa taken by them is half that of dahi - bhalla. The cost of one plate of gol - gappa was Rs. 10 and cost of one plate of dahi - bhalla was Rs. 5. She spent Rs. 60. Represent the situation algebraically and graphically.

Let no. of plates of gol - gappa = x


and no. of plates of dhai - bhalla = y


Cost of 1 plate gol - gappa = Rs. 10


Cost of 1 plate dhai - bhalla = Rs. 5


Total money spent = Rs. 20


According to the question,


…(1)


10x + 5y = 60 …(2)


From eqn (1), we get


2x – y = 0 …(3)


Now, table for 2x – y = 0



Now, table for 10x + 5y = 60



On plotting points on a graph paper and join them to get a straight line representing .


Similarly, on plotting the points on the same graph paper and join them to get a straight line representing 10x + 5y = 60.



Here, the lines representing Eq. (1) and Eq. (2) intersecting at point A i.e. (3,6).


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