Q40 of 44 Page 4

A typist charges ₹ 145 for typing 10 English and 3 Hindi pages, while charges for typing 3 English and 10 Hindi pages are ₹ 180. Using matrices, find the charges of typing one English and one Hindi page separately. However, typist charged only ₹ 2 per page from a poor student Shyam for 5 Hindi pages. How much less charged from this poor boy? Which values are reflected in this problem?(CBSE 2016)

Let the cost of typing 1 English page be x.


The cost of typing 1 Hindi page is y.


Then 10x + 3y = 145... (1) × 10


3x + 10y = 180. ... (2) × 3


from 1 and 2 we get


100x + 30y = 1450


9x + 30y = 540


- - -


by solving we get


91x = 910


× = 910/91


× = 10


(1) 10x + 3y = 145


10 (10) + 3y = 145


3y = 145 - 100 = 45


y = 45/3 = 15


So x = 10 and y = 15.


Actual Rate = 15 × 5 = 75


Amount taken from shyam = 2 × 5 = 10


Difference = 75 - 10 = 65


He charged 65 less to shyam


Humanity and helping poor people is reflected here.

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