Percentage [प्रतिशत]–06

Question: The tax on commodity is diminished by 20% and its consumption increases by 15%. Find the effect on revenue. [किसी वस्तु पर लगाये जाने वाले कर में 20%की कमी की जाती है एवं उसकी खपत में 15% की वृद्धि होती है. राजस्व पर कितना प्रभाव पड़ता है?] [Ans. (b) 8% decrease]                                                                                                                    

(a) 8% increase (b) 8% decrease (c) 12% increase (d) 12% decrease  (e) none of these

Solution:

Detailed Explanation: 

First Method: Let the revenue of the government be 100 units. If tax is diminished by 20%, the revenue will also be decreased by 20%, so it will be 100-20 = 80.

If consumption is increased by 15%, then the revenue will be increased%, so the resultant revenue will be 80 +15% of 80 = 80 +12 = 92  Therefore, the change = 92 - 100 = - 8   So,  the decrease is 8%.  Ans.

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Second Method: When any quantity is changed by x% and y% successively, then the quantity is changed by

x+y+(xy)/100

So, the change is -20+15+{(-20)×(15)}/100 = - 8%.

Therefore, 8% decrease is the answer.

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