Aptitude :: PercentagePage 3
17.  10% of the inhabitants of a village having died of cholera, a panic set in, during which 25% of the remaining inhabitants left the village. The population is the reduced to 4050. Find the number of original inhabitants?  (a)4000  (b)5000  (c)7000  (d)6000 

Answer is: DLet, the total number of original inhabitants be x.
Then, (100  25)% of (100  10)% of x = 4050.
(75/100) X (90/100) X x = 4050.
(27/40) X x = 4050.
x = 6000.
18.  A salesman's commission is 5% on all sales upto Rs. 10000 and 4% on all sales exceeding this. He remits Rs. 31000 to his parent company after deducting his commission. Find the total sales?  (a)32500  (b)33000  (c)34000  (d)35400 

Answer is: ALet his total sales be Rs. x.
Now (Total Sales)  (commission) = 31100.
∴ x  [(5/100) X 10000 + (4/100)(x  10000)] = 31100
x  500  [(x  10000)/25] = 31100.
x  (x/25) = 31200.
x = Rs. 32500.
19.  Raman's salary was decreased by 50% and subsequently increases by 50%. How much percentage does he lose ?  (a)10%  (b)15%  (c)20%  (d)25% 

Answer is: DLet, Original salary Rs. 100.
New final salary = 150% of (50% of Rs. 100).
New final salary = Rs. (150/100) X (50/100) X 100.
New final salary = Rs. 75.
∴ decreased by 25%
20.  The salary of a person was reduced by 10%. By what percent should reduced salary be raised so as to bring it at par with his original salary ?  (a)82/9%  (b)91/9%  (c)100/9%  (d)109/9% 

Answer is: CLet, the original salary be 100.
Then, New salary = 90.
Increase of 90 = 10.
Increase on 100 = (10/90) X 100 = 100/9%
21.  If the new budget, the price of kerosene oil rise by 25%. By how much percent must a person reduce his consumption so that his expenditure on it does not increase ?  (a)10%  (b)20%  (c)30%  (d)40% 

Answer is: BLet, Reduction in consumption = [(R/(100 + R))% X 100] X 100%
Reduction in consumption = (25/125)% X 100% = 20%
22.  Ravi spends 75% of his income. His income is increased by 20% and he increased his expenditure by 10%. Find the percentage in increase in his savings.  (a)50%  (b)60%  (c)70%  (d)80% 

Answer is: ALet, original income = 100.
Then, expenditure = 75 and saving 25.
New income = 120, New expenditure = (110/100) X 75 = 165/2.
New saving = (75/2)  25 = 25/2.
∴ Increase saving = (25/2) X (1/25) X 100 = 50%
23.  The population of a town is 176400. If it increase at the rate of 5% per annum, what will be its population 2 years hence?  (a)19000  (b)19400  (c)19448  (d)20000 

Answer is: CPopulation after 2 years = 176400 X [1 + 5/100]^{2}.
Population after 2 years = 176400 X 21/20 X 21/20
Population after 2 year = 19448.
24.  If A's salary is 20% less than B's salary more than A's ?  (a)10%  (b)15%  (c)20%  (d)25% 

Answer is: DRequired percentage = [20/100  20] X 100%.
Required percentage = 25%
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