Exercise 16.3

A bucket is in the form of a frustum of a cone of height $30cm$ with radii of its lower and upper ends as $10cm$and $20cm$ respectively. Find the capacity and surface area of the bucket. Also, find the cost of milk which can completely fill the container, at the rate of $Rs.25$ per litre.

Let us assume  R and r be the radii of the top and base of the bucket respectively, Let us assume h be its height of the bucket. Then, according to the question we have $R=20cm$, $r=10cm$, $h=30cm$...

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A milk container of height $16cm$ is made of metal sheet in the form of frustum of a cone with radii of its lower and upper ends as $8cm$ and $20cm$ respectively. Find the cost of milk at the rate of $Rs.44$ per liter which the container can hold.

As per the given information, A milk container in a form of frustum of a cone with, Radius of the lower end $\left( {{r}_{1}} \right)=8cm$ And radius of the upper end $\left( {{r}_{2}} \right)=20cm$...

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A tent consists of a frustum of a cone capped by a cone. If radii of the ends of the frustum be $13m$ and $7m$, the height of frustum be $8m$ and the slant height of the conical cap be $12m$, find the canvas required for the tent.

According to the given data in the question, Height of frustum (h) $=8m$ (given) Bigger and smaller radii of the frustum cone are $13cm$ and $7cm$. Therefore, ${{r}_{1}}=13cm$ and ${{r}_{2}}=7cm$...

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The height of a cone is $20cm$. A small cone is cut off from the top by a plane parallel to the base. If its volume be $1/125$ of the volume of the original cone, determine at what height above the base the section is made.

According to the given information, Let us asssume the radius of the small cone be r cm And, the radius of the big cone be R cm It is given, height of the big cone is $20cm$ Let us also assume the...

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The height of a cone is $20cm$. A small cone is cut off from the top by a plane parallel to the base. If its volume be $1/125$ of the volume of the original cone, determine at what height above the base the section is made.

According to the given information, Let us asssume the radius of the small cone be r cm And, the radius of the big cone be R cm It is given, height of the big cone is $20cm$ Let us also assume the...

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A bucket has top and bottom diameters of $40cm$ and $20cm$ respectively. Find the volume of the bucket if its depth is $12cm$. Also, find the cost of tin sheet used for making the bucket at the rate of $Rs120$ per$d{{m}^{2}}$

As per the given information, Diameter of the top of the bucket $=40cm$ So, the radius of the top of the bucket $\left( {{r}_{1}} \right)$ $=40/2=20cm$ Diameter of the bottom part of the bucket...

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