Answer

Verified

339.6k+ views

**Hint:**From the given data we conclude that Kiya wants to cover a cuboid box with square sheets. In order to cover the box we first need to find the total surface area of the box. And then the area of one square sheet. Because the number of square sheets required will be decided by the total surface area of the box she wants to cover for her project.

**Formula used:**

1. Number of square sheets required = \[\dfrac{{the{\text{ }}total{\text{ }}surface{\text{ }}area{\text{ }}of{\text{ }}the{\text{ }}box}}{{the{\text{ }}area{\text{ }}of{\text{ }}one{\text{ }}square{\text{ }}sheet.}}\]

2. Total surface area of the cuboid = \[2\left( {lb + bh + hl} \right)\]

3. Area of square = \[side \times side\]

**Step by step solution:**

First let’s find the total surface area of the cuboidal box Kiya wants to cover.

Total surface area of the cuboid = \[2\left( {lb + bh + hl} \right)\]

Given that,

l=80cm, b=40cm and h=20cm

Putting these values,

\[{A_{cuboid box}} \Rightarrow 2\left( {80 \times 40 + 40 \times 20 + 20 \times 80} \right)\]

On multiplying,

\[ \Rightarrow 2\left( {3200 + 800 + 1600} \right)\]

\[ \Rightarrow 2 \times 5600\]

\[ \Rightarrow 11200c{m^2}\]

This is the total surface area of the box. Now let’s find the area of the sheet.

We know that area of the square sheet is given by

Area of square = \[side \times side\]

Side of the square sheet is 40cm.

\[{A_{sheet}} \Rightarrow 40 \times 40\]

\[ \Rightarrow 1600c{m^2}\]

This is the area of the sheet.

Now the main task is to find the number of such sheets required.

Number of square sheets required = \[\dfrac{{the{\text{ }}total{\text{ }}surface{\text{ }}area{\text{ }}of{\text{ }}the{\text{ }}box}}{{the{\text{ }}area{\text{ }}of{\text{ }}one{\text{ }}square{\text{ }}sheet.}}\]

\[ \Rightarrow \dfrac{{11200}}{{1600}}\]

Cancelling the zeros

\[ \Rightarrow \dfrac{{112}}{{16}}\]

On dividing by 16 we get,

\[ \Rightarrow 7\]

**This is the number of sheets required 7.**

**Note:**

From the dimensions of the box we conclude that it is a cuboid box. Note that we have found the total surface area of the cuboid box because it is to be covered from all sides by the sheet paper. An area of sheet paper is calculated because it is to be covered on the box.

Recently Updated Pages

Three beakers labelled as A B and C each containing 25 mL of water were taken A small amount of NaOH anhydrous CuSO4 and NaCl were added to the beakers A B and C respectively It was observed that there was an increase in the temperature of the solutions contained in beakers A and B whereas in case of beaker C the temperature of the solution falls Which one of the following statements isarecorrect i In beakers A and B exothermic process has occurred ii In beakers A and B endothermic process has occurred iii In beaker C exothermic process has occurred iv In beaker C endothermic process has occurred

The Equation xxx + 2 is Satisfied when x is Equal to Class 10 Maths

Define absolute refractive index of a medium

Find out what do the algal bloom and redtides sign class 10 biology CBSE

Prove that the function fleft x right xn is continuous class 12 maths CBSE

Find the values of other five trigonometric functions class 10 maths CBSE

Trending doubts

How do you solve x2 11x + 28 0 using the quadratic class 10 maths CBSE

Fill the blanks with the suitable prepositions 1 The class 9 english CBSE

Difference between Prokaryotic cell and Eukaryotic class 11 biology CBSE

Write a book review which you have recently read in class 8 english CBSE

Difference Between Plant Cell and Animal Cell

Describe the poetic devices used in the poem Aunt Jennifers class 12 english CBSE

Change the following sentences into negative and interrogative class 10 english CBSE

State the laws of reflection of light

What I want should not be confused with total inactivity class 12 english CBSE