What is 10% of 20% of 25% of 100?
30% of a% of b is 25% of b% of c. Which of the following is c?
= 30a = 25c, c = 1.2a
When 40% of a number E is added to another number R, B becomes 125% of its previous value. Then which of the following is true regarding the values of E and R?
i.e. 0.4E = 0.25R -> E / R = 5 / 8
Apparently, it seems that R is bigger, but if you consider E and R to be negative the opposite would be true.
Hence, option (c) is correct.
In an election between 2 candidates, Walter gets 80% of the total valid votes. If the total votes were 12000, what is the number of valid votes that the other candidate Jesse Pinkman gets if 15% of the total votes were declared invalid?
Walter gets 80% of 10200 votes = 8160 votes and Jesse Pinkman would get 10200 – 8160 = 2040 Votes.
A number is mistakenly divided by 2 instead of being multiplied by 2. Find the percentage change in the result due to this mistake.
Hence, the percentage change in the result is 1.5x X 100 / 2x. Clearly, the value would be 75%. (Note: In this case, the percentage change in the answer does not depend on the value of ‘x’).
In a mixture of 100 litres of milk and water, 25% of the mixture is milk. How much water should be added to the mixture so that milk becomes 20% of the mixture?
Thus, the amount in the total mixture must be 125, which means we need to add 25 litres of water to make 100 litres of the mixture.
10% of Mexico’s population migrated to South Asia, 10% of the remaining migrated to America and 10% of the rest migrated to Australia. If the female population, which was left in Mexico, remained only 3,64,500, find the population of Mexico City before the migration and its effects if it is given that before the migration the female population was half the male population and this ratio did not change after the migration?
After people migrated to south Asia - 0.9x
After people migrated to America - 0.81x
After people migrated to Australia - 0.729x
After the migrations, 72.9% of the people would remain in the country. This would comprise females and males in the ratio of 1:2 (as given) and hence, the women’s population left would be 1/3rd of 72.9% = 24.3% which is given as being equal to 364500. Thus, the total population would be
364500 X 100 / 24.3 = 1500000
If the length, breadth and height of a cube are decreased, decreased and increased by 5%, 5% and 20%, respectively, then what will be the impact on the surface area of the cube (in percentage terms)?
A percentage increase of 6.0833%.
The price of raw materials has gone up by 15%, labour cost has also increased from 25% of the cost of raw material to 30% of the cost of raw material. By how much percentage should there be a reduction in the usage of raw materials so as to keep the cost the same?
The total cost initially would be 125.
The total cost for the same usage of raw material would now be: 115 + 34.5 = 149.5
This cost has to be reduced to 125. The percentage reduction will be given by 24.5 / 149.5 = 17 % approx.
There are three galleries in a coal mine. On the first day, two galleries are operative and after some time, the third gallery is made operative. With this, the output of the mine became half as large again. What is the capacity of the second gallery as a percentage of the first, if it is given that a four-month output of the first and the third galleries was the same as the annual output of the second gallery?
The third gallery making the capacity ‘half as large again’ means an increase of 50%.
Further, it is given that: 4(first + third) = 12 (second) In order to get to the correct answer, try to fit in the options into this situation.
(Note here that the question is asking you to find the capacity of the second gallery as a percentage of the first.)
If we assume option (a) as correct – 70% the following solution follows:
If the second is 70, then first is 100 and the first + second is 170. Then third will be 85 (50% of first + second). Then the equation:
4 X (100 + 85) should be equal to 12 X 70
But this is not true.
Through trial and error, you can see that the third option fits correctly.
4 X (100 + 80) = 12 X 60.
Hence, it is the correct answer.