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**irspow****Member**- Registered: 2005-11-24
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I’d like to add a big thank you for posting all the questions too.

*Last edited by irspow (2021-01-26 06:14:47)*

I am at an age where I have forgotten more than I remember, but I still pretend to know it all.

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 33,310

Hi,

irspow wrote:

I’d like to add a big thank you for posting all the questions too.

My pleasure, irspow!

Solution M#616 : Excellent!

M#617. All the edges of a square pyramid are of equal lengths. If the length of the base is 30 centimeters,

(a) find the slant height.

(b) find the lateral surface area.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**irspow****Member**- Registered: 2005-11-24
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I am at an age where I have forgotten more than I remember, but I still pretend to know it all.

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 33,310

Hi,

.

Excellent!

M#618. The slant height of a frustum of a cone is 4 cm and perimeter (circumference) of its circular ends are 18 cm and 6 cm. Find the curved surface area of the frustum.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**irspow****Member**- Registered: 2005-11-24
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*Last edited by irspow (2021-01-29 11:00:33)*

I am at an age where I have forgotten more than I remember, but I still pretend to know it all.

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 33,310

Hi,

Excellent!

M#619. A circular sheet of radius 18 centimetres is divided into 9 equal areas.

(a) Find the measure of the central angle of a sector.

(b) Find the slant height of a cone which can be made by a sector.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**irspow****Member**- Registered: 2005-11-24
- Posts: 1,055

I am at an age where I have forgotten more than I remember, but I still pretend to know it all.

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 33,310

Hi,

Neat work!

M#620. The base area of a cone is

cm and curved surface area is . Calculate the total surface area.Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**irspow****Member**- Registered: 2005-11-24
- Posts: 1,055

I am at an age where I have forgotten more than I remember, but I still pretend to know it all.

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 33,310

Hi,

Good work!

M#621. What is the change in volume of a sphere if its radius becomes three times?

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**irspow****Member**- Registered: 2005-11-24
- Posts: 1,055

I am at an age where I have forgotten more than I remember, but I still pretend to know it all.

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 33,310

Hi,

Neat work!

M#622.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**irspow****Member**- Registered: 2005-11-24
- Posts: 1,055

I am at an age where I have forgotten more than I remember, but I still pretend to know it all.

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 33,310

Hi

Neat work!

M#623. A rectangular park 100 m by 20 m has a gravel path 2 m wide on all four sides, outside the path. Find the area of the path.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**irspow****Member**- Registered: 2005-11-24
- Posts: 1,055

I am at an age where I have forgotten more than I remember, but I still pretend to know it all.

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 33,310

Hi,

Neat work!

M#624. A rectangular field 172 m by 58 m has a path of uniform width, inside all the four sides.Find the width of the path.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**irspow****Member**- Registered: 2005-11-24
- Posts: 1,055

I am at an age where I have forgotten more than I remember, but I still pretend to know it all.

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**ganesh****Administrator**- Registered: 2005-06-28
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Hi,

Edited : M#624. A rectangular field 172 m by 58 m has a path of uniform width, inside all the four sides. The area of the path is 1125 square metres. Find the width of the path.

Inconvenience regretted.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**irspow****Member**- Registered: 2005-11-24
- Posts: 1,055

I am at an age where I have forgotten more than I remember, but I still pretend to know it all.

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 33,310

Hi,

Excellent!

M#625. The ratio of the length and breadth of a room is 3 : 1. If the height of the room is 13 meters while the area of its four walls is 1664 square meters, then find the area of the ceiling.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**irspow****Member**- Registered: 2005-11-24
- Posts: 1,055

I am at an age where I have forgotten more than I remember, but I still pretend to know it all.

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 33,310

Hi,

Neat work!

M#626. The area of a rectangular field is 0.5 hectare. If the field is 5 kilometers long, then find the width of the field.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**irspow****Member**- Registered: 2005-11-24
- Posts: 1,055

I am at an age where I have forgotten more than I remember, but I still pretend to know it all.

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 33,310

Hi,

Neat work!

M#627. The perimeter of the floor of a room is 18 meters. What is the area of the walls of the room, if the height of the room is 3 meters?

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**irspow****Member**- Registered: 2005-11-24
- Posts: 1,055

I am at an age where I have forgotten more than I remember, but I still pretend to know it all.

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