Percentage All Competence Aptitude
Question 11
The strength of a school increases and decreases in every alternate year by 10%. It started with increase in 2000. Then the strength of the school in 2003 as compared to that in 2000 was ?
Let's denote the initial strength of the school in 2000 as \( S \).
- In 2001, there is a 10% increase, so the strength becomes \( 1.1S \).
- In 2002, there is a 10% decrease, so the strength becomes \( 0.9 \times 1.1S = 0.99S \).
- In 2003, there is a 10% increase, so the strength becomes \( 1.1 \times 0.99S = 1.089S \).
Now, let's find the percentage change in the strength from 2000 to 2003:
\[ \text{Percentage Change} = \left( \dfrac{\text{Final Strength} - \text{Initial Strength}}{\text{Initial Strength}} \right) \times 100 \]
\[ \text{Percentage Change} = \left( \dfrac{1.089S - S}{S} \right) \times 100 \]
\[ \text{Percentage Change} = \left( \dfrac{0.089S}{S} \right) \times 100 \]
\[ \text{Percentage Change} = 8.9\% \]
Therefore, the strength of the school in 2003 as compared to 2000 increased by 8.9%. Hence, the correct option is "increased by 8.9%".
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Question 12
In an office 40% of the staff is female, 40% of the females and 60% of the males voted for me. The percentage of votes I got was ?
Let's denote the total number of staff as \( S \), the number of females as \( F \), and the number of males as \( M \).
1. \( 40\% \) of the staff is female, so the number of females (\( F \)) is \( 0.4 \times S \).
\[ F = 0.4S \]
2. \( 60\% \) of the staff is male, so the number of males (\( M \)) is \( 0.6 \times S \).
\[ M = 0.6S \]
3. \( 40\% \) of the females voted for you, so the number of female votes is \( 0.4 \times F \).
\[ \text{Female votes} = 0.4 \times 0.4S \]
4. \( 60\% \) of the males voted for you, so the number of male votes is \( 0.6 \times M \).
\[ \text{Male votes} = 0.6 \times 0.6S \]
Now, let's find the total number of votes (\( \text{Total votes} \)):
\[ \text{Total votes} = \text{Female votes} + \text{Male votes} \]
\[ \text{Total votes} = 0.4 \times 0.4S + 0.6 \times 0.6S \]
Simplify the expression:
\[ \text{Total votes} = 0.16S + 0.36S \]
\[ \text{Total votes} = 0.52S \]
Now, find the percentage of votes you got:
\[ \text{Percentage of votes} = \left( \dfrac{\text{Total votes}}{\text{Total staff}} \right) \times 100 \]
\[ \text{Percentage of votes} = \left( \dfrac{0.52S}{S} \right) \times 100 \]
\[ \text{Percentage of votes} = 52\% \]
Therefore, the percentage of votes you got was \( 52\% \). Hence, the correct option is "52%".
Not clear enough?
Question 13
If a man receives on one-fourth of his capital 3% interest, on two third 5% and on the remainder 11%, the percentage he receives on the whole is ?
Let's denote the capital as C. According to the given information:
1. One-fourth of the capital receives 3% interest, which is (1/4) * C * 3/100.
2. Two-thirds of the capital receives 5% interest, which is (2/3) * C * 5/100.
3. The remainder (1 - 1/4 - 2/3) receives 11% interest, which is (1/12) * C * 11/100.
Now, let's add these interest amounts to find the total interest:
\[ \text{Total Interest} = \dfrac{1}{4} \cdot C \cdot \dfrac{3}{100} + \dfrac{2}{3} \cdot C \cdot \dfrac{5}{100} + \dfrac{1}{12} \cdot C \cdot \dfrac{11}{100} \]
Combine the terms:
\[ \text{Total Interest} = \dfrac{3C}{400} + \dfrac{10C}{300} + \dfrac{11C}{1200} \]
Now, find a common denominator:
\[ \text{Total Interest} = \dfrac{9C + 40C + 11C}{1200} \]
\[ \text{Total Interest} = \dfrac{60C}{1200} \]
Simplify:
\[ \text{Total Interest} = \dfrac{1}{20}C \]
To find the percentage, divide the total interest by the capital and multiply by 100:
\[ \text{Percentage} = \dfrac{\dfrac{1}{20}C}{C} \times 100 \]
\[ \text{Percentage} = \dfrac{1}{20} \times 100 \]
\[ \text{Percentage} = 5 \]
So, the percentage he receives on the whole is 5%. Therefore, the correct answer is 5.
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Question 14
Due to an increase of 50% in the price of eggs, 4 eggs less are available for 24. The present rate of eggs per dozen is ?
Let's denote the original price of eggs as \(P\) per dozen.
Due to a 50% increase, the new price (\(P_{\text{new}}\)) is given by:
\[ P_{\text{new}} = P + 0.5 \times P = 1.5P \]
Now, the number of eggs available for the original price is \(12\) (a dozen). Due to a 50% increase in price, 4 eggs less are available for the new price.
So, the number of eggs available for the new price is \(12 - 4 = 8\).
Now, we can set up the equation:
\[ P_{\text{new}} \times \left( \dfrac{8}{12} \right) = 24 \]
Substitute the expression for \(P_{\text{new}}\):
\[ 1.5P \times \left( \dfrac{8}{12} \right) = 24 \]
Solving for \(P\):
\[ 1.5P \times \dfrac{2}{3} = 24 \]
\[ P = \dfrac{24 \times 3}{1.5 \times 2} \]
\[ P = 36 \]
So, the original rate of eggs per dozen (\(P\)) is 36. Therefore, the correct answer is 36.
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Question 15
An individual pays 30% income tax. On this tax he has to pay a surcharge of 10%. Thus, the net tax rate, he has to pay, is ?
Let's denote the income before tax as \( I \). The individual pays 30% income tax on this amount, so the tax paid (\( T \)) is given by:
\[ T = 0.30 \times I \]
Now, there is a surcharge of 10% on this tax, so the total tax paid (\( \text{Total Tax} \)) is:
\[ \text{Total Tax} = T + 0.10 \times T \]
\[ \text{Total Tax} = 1.10 \times T \]
Substitute the expression for \( T \):
\[ \text{Total Tax} = 1.10 \times (0.30 \times I) \]
\[ \text{Total Tax} = 0.33 \times I \]
Now, to find the net tax rate, we need to calculate the percentage of the total tax with respect to the original income:
\[ \text{Net Tax Rate} = \left( \dfrac{\text{Total Tax}}{I} \right) \times 100 \]
\[ \text{Net Tax Rate} = \left( \dfrac{0.33 \times I}{I} \right) \times 100 \]
\[ \text{Net Tax Rate} = 33\% \]
Therefore, the net tax rate the individual has to pay is 33%. The closest option is 33%, so the correct answer is:
\[ \text{Net Tax Rate} = 33\% \]
Not clear enough?
Question 16
A man bought some eggs of which 10% are rotten. He gives 80% of the remainder to his neighbours. Now he is left out with 36 eggs. How many eggs he bought ?
Let's denote the number of eggs the man bought as \( E \).
1. Initially, 10% of the eggs are rotten, so the remaining good eggs are \( 90\% \) of the total:
\[ \text{Good eggs after first step} = 0.9 \times E \]
2. The man gives 80% of the remaining eggs to his neighbors, so the eggs he has left are \( 20\% \) of the good eggs after the first step:
\[ \text{Eggs left after second step} = 0.2 \times (0.9 \times E) \]
According to the given information, he is left with 36 eggs:
\[ 0.2 \times (0.9 \times E) = 36 \]
Now, solve for \( E \):
\[ E = \dfrac{36}{0.2 \times 0.9} \]
\[ E = \dfrac{36}{0.18} \]
\[ E = 200 \]
Therefore, the man initially bought 200 eggs. So, the correct answer is 200.
Not clear enough?
Question 17
A Set A consists of integers 27, 28, 30, 32, and 33. If integer k is included in the average of set A will increase by 30%. What is the value of integer K ?
Let's denote the average of the original set A as \( \bar{A} \).
The average of a set is calculated by summing up all the values in the set and then dividing by the number of values.
\[ \bar{A} = \dfrac{27 + 28 + 30 + 32 + 33}{5} \]
Now, if we include integer \( k \) and the average increases by 30%, the new average (\( \bar{A'} \)) is given by:
\[ \bar{A'} = 1.3 \times \bar{A} \]
Now, we can set up the equation:
\[ \dfrac{27 + 28 + 30 + 32 + 33 + k}{6} = 1.3 \times \bar{A} \]
Plug in the expression for \( \bar{A} \):
\[ \dfrac{150 + k}{6} = 1.3 \times \left( \dfrac{150}{5} \right) \]
Solve for \( k \):
\[ \dfrac{150 + k}{6} = 1.3 \times 30 \]
\[ 150 + k = 6 \times 39 \]
\[ 150 + k = 234 \]
\[ k = 84 \]
Therefore, the value of integer \( k \) is 84. So, the correct answer is 84.
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Question 18
A man received 8,80,000 as his annual salary of the year 2007 which was 10% more than his annual salary in 2006. His annual salary in the year 2006 was ?
Let the annual salary in the year 2006 be \(S\). According to the given information, the annual salary in 2007 is 10% more than that in 2006, so:
\[ \text{Salary in 2007} = S + 0.10 \times S \]
Given that the salary in 2007 is \(8,80,000\), we can set up the equation:
\[ 8,80,000 = S + 0.10 \times S \]
Combine like terms:
\[ 8,80,000 = 1.10 \times S \]
Now, solve for \(S\):
\[ S = \dfrac{8,80,000}{1.10} \]
\[ S = 8,00,000 \]
Therefore, the annual salary in the year 2006 was \(8,00,000\). So, the correct answer is \(8,00,000\).
Not clear enough?
Question 19
If each side of a cube is increased by 10% the volume of the cube will increase by ?
Let \(S\) be the original side length of the cube, and \(V\) be the original volume of the cube.
The original volume \(V\) is given by \(V = S^3\).
If each side of the cube is increased by 10%, the new side length (\(S_{\text{new}}\)) will be \(1.10 \times S\). The new volume (\(V_{\text{new}}\)) is given by \((1.10 \times S)^3\).
Now, let's find the percentage increase in volume:
\[ \text{Percentage Increase} = \left( \dfrac{V_{\text{new}} - V}{V} \right) \times 100 \]
\[ \text{Percentage Increase} = \left( \dfrac{(1.10 \times S)^3 - S^3}{S^3} \right) \times 100 \]
\[ \text{Percentage Increase} = \left( \dfrac{1.331 \times S^3 - S^3}{S^3} \right) \times 100 \]
\[ \text{Percentage Increase} = \left( \dfrac{0.331 \times S^3}{S^3} \right) \times 100 \]
\[ \text{Percentage Increase} = 33.1\% \]
Therefore, if each side of a cube is increased by 10%, the volume of the cube will increase by 33.1%. So, the correct answer is 33.1%.
Not clear enough?
Question 20
In an examination A got 25% marks more than B, B got 10% less than C and C got 25% more than D. If D got 320 marks out of 500, the marks obtained by A were ?
Let's denote the marks obtained by D as \(D\), by C as \(C\), by B as \(B\), and by A as \(A\).
Given information:
1. \(C\) got 25% more than \(D\), so \(C = D + 0.25D = 1.25D\).
2. \(B\) got 10% less than \(C\), so \(B = C - 0.10C = 0.90C\).
3. \(A\) got 25% more than \(B\), so \(A = B + 0.25B = 1.25B\).
4. \(D\) got 320 marks out of 500, so \(D = 320\).
Now, let's calculate \(C\):\[ C = 1.25D = 1.25 \times 320 \]
\[ C = 400 \]
Now, let's calculate \(B\):\[ B = 0.90C = 0.90 \times 400 \]
\[ B = 360 \]
Finally, let's calculate \(A\):\[ A = 1.25B = 1.25 \times 360 \]
\[ A = 450 \]
Therefore, the marks obtained by A were 450. So, the correct answer is 450.
Not clear enough?
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| Maina Merchants Trading and Profit and Loss Account (Extract) | |||||||||||||||||||||||||
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Maina Merchants Trading and Profit and Loss Account (Extract) Determine the closing stock based on the provided table.
\[
\begin{array}{|l|r|}
\hline
\text{Opening Stock} & 50,000 \\
\text{Purchases} & 200,000 \\
\text{Sales} & 350,000 \\
\text{Closing Stock} & 80,000 \\
\hline
\end{array}
\]
What is the cost of good sold?
