All Exams Test series for 1 year @ ₹349 only
Question

The length, breadth and height of a cuboid are increased by 10%, 20% and 50% respectively. What is the percentage increase in volume of the cuboid?

This question was previously asked in
CDS 2 2024 Maths Question Paper (01-Sep-2024)
The correct answer is
98%

Cuboid Volume Calculation Explained

This problem asks us to find the overall percentage increase in the volume of a cuboid after its dimensions (length, breadth, and height) are increased by different percentages.

Understanding Cuboid Volume

The volume of a cuboid is calculated by multiplying its length, breadth, and height.

If the original dimensions are L (length), B (breadth), and H (height), the original volume (\(V_1\)) is given by:

\( V_1 = L \times B \times H \)

Calculating New Dimensions

The problem states the following increases:

  • Length increases by 10%.
  • Breadth increases by 20%.
  • Height increases by 50%.

Let's calculate the new dimensions (\(L'\), \(B'\), \(H'\)):

  • New Length (\(L'\)): The original length L is increased by 10%.
    \( L' = L + (10\% \text{ of } L) = L + \frac{10}{100} L = L(1 + 0.10) = 1.1 L \)
  • New Breadth (\(B'\)): The original breadth B is increased by 20%.
    \( B' = B + (20\% \text{ of } B) = B + \frac{20}{100} B = B(1 + 0.20) = 1.2 B \)
  • New Height (\(H'\)): The original height H is increased by 50%.
    \( H' = H + (50\% \text{ of } H) = H + \frac{50}{100} H = H(1 + 0.50) = 1.5 H \)

Calculating New Volume

The new volume (\(V_2\)) is calculated using the new dimensions:

\( V_2 = L' \times B' \times H' \)

Substituting the expressions for \(L'\), \(B'\), and \(H'\):

\( V_2 = (1.1 L) \times (1.2 B) \times (1.5 H) \)

Rearranging the terms:

\( V_2 = (1.1 \times 1.2 \times 1.5) \times (L \times B \times H) \)

First, calculate the product of the multipliers:

\( 1.1 \times 1.2 = 1.32 \)

\( 1.32 \times 1.5 = 1.98 \)

So, the new volume is:

\( V_2 = 1.98 \times (L \times B \times H) \)

Since \(V_1 = L \times B \times H\), we have:

\( V_2 = 1.98 V_1 \)

Determining Percentage Increase

The increase in volume is \(V_2 - V_1\).

The percentage increase is calculated as:

\( \text{Percentage Increase} = \frac{V_2 - V_1}{V_1} \times 100\% \)

Substitute \(V_2 = 1.98 V_1\):

\( \text{Percentage Increase} = \frac{1.98 V_1 - V_1}{V_1} \times 100\% \)

\( \text{Percentage Increase} = \frac{(1.98 - 1) V_1}{V_1} \times 100\% \)

\( \text{Percentage Increase} = \frac{0.98 V_1}{V_1} \times 100\% \)

\( \text{Percentage Increase} = 0.98 \times 100\% \)

\( \text{Percentage Increase} = 98\% \)

Conclusion

The volume of the cuboid increases by 98%.

Was this answer helpful?

Similar Questions

  1. There are two employees X and Y. X's salary is first increased by 12% and then decreased by 10%, and Y's salary is first increased by 10% and then decreased by 12%. If their salaries at present are equal, then what was the ratio of initial salary of X to initial salary of Y?
  2. 100 quintals is what percent of 10 metric tonnes?

  3. The total population of an area is 10,000 out of which males and females are equal in number. Out of the total population 30% are Newspaper readers. Out of the total newspaper readers, one-third read English Newspaper. Out of the total English Newspaper readers, 20% are females. What is the number of males who do not read English Newspaper?
  4. What is the square root of 64%?
  5. In a village consisting of \(p\) persons, \(x\)% can read and write. Of the males, only \(y\)% can read and write. Of the females, only \(z\)% can read and write. If \(x, y > z\), then what is the number of males in the village?
  6. A reduction of 10% in the price of sugar enables a person to buy 6·2 kg more for \(₹2790\). What is the reduced price per kilogram ?
  7. What is the percentage of copper in X ?
  8. What is the percentage of zinc in X ?

Important Questions from Percentage

  1. In an examination, 25% of the candidates failed in Mathematics and 12% failed in English. If 10% of the candidates failed in both the subjects and 292 candidates passed in both the subjects, which one of the following is the number of total candidates appeared in the examination?

  2. What is the value of 9% of 5500 + 2.4% of 1100 - 40% of 1600?

  3. Population of a village is 7960 in which 4660 are female. If in that village 60% are literate in which 70% female are literate, then what is the number of literate male ?

  4. The numbers of students of three classes of a school are in the ratio 4 : 5 : 6. If numbers of students in these classes increase by 25%, 20% and 25% respectively, then ratio of numbers of students will become:

  5. In an examination, Ram obtained 20 % more than Ashok but 10% less than Rajesh. If the marks obtained by Ashok is 1080. Then the Percentage marks obtained by Rajesh if the full marks is 2000 ;

Need Expert Advice?
Test Series
CDS img
Defence
UPSC CDS 2026 Mock Test Series
536 Tests 4 Tests Free
1647 Attempts
4.3(174)
English, Hindi
More Questions from CDS

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App