The image above is a conical frustum.

To compute the lateral surface area of a conical frustum requires three essential parameters which are the radius of the lower base (R), radius of the upper base (r) and the height (h).

The formula for calculating the lateral surface area of a conical frustum:

A = π(R + r)√((R – r)² + h²)

Where;

A = Area of the conical frustum

R = Radius of the lower base

r = Radius of the upper base

h = Height of the conical frustum

Let’s solve an example;

Given that the height of a conical frustum is 28 cm with a radius of lower base of 22 cm and a radius of upper base of 19 cm. Find the lateral surface area of the conical frustum?

This implies that;

h = Height of the conical frustum = 28 cm

R = Radius of the lower base = 22 cm

r = Radius of the upper base = 19 cm

A = π(R + r)√((R – r)² + h²)

A = 3.142(22 + 19)√((22 – 19)² + 28²)

A = 3.142(41)√((3)² + 28²)

A = 3.142 (41)√(9 + 784)

A = 3.142 (41)√(793)

A = 3.142 (41)(28.16)

A = 3.142 x 1154.56

A = 3627.63

Therefore, the** lateral surface area of the conical frustum** is **3627.63 cm².**

Nickzom Calculator – **The Calculator Encyclopedia** is capable of calculating the lateral surface area of a conical frustum.

To get the answer and workings of the lateral surface area of a conical frustum using the **Nickzom Calculator – The Calculator Encyclopedia. **First, you need to obtain the app.

You can get this app via any of these means:

**Web** – https://www.nickzom.org/calculator-plus

To get access to the **professional **version via web, you need to **register** and **subscribe **for** NGN 1,500 **per** annum** to have utter access to all functionalities.

You can also try the **demo **version via https://www.nickzom.org/calculator

**Android (Paid)** – https://play.google.com/store/apps/details?id=org.nickzom.nickzomcalculator

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**Apple (Paid)** – https://itunes.apple.com/us/app/nickzom-calculator/id1331162702?mt=8

Once, you have obtained the calculator encyclopedia app, proceed to the **Calculator Map, **then click on **Mensuration**** **under the **Mathematics** section.

Now, click on **Lateral Surface area of a conical frustum** under **Mensuration**

The screenshot below displays the page or activity to enter your values, to get the answer for the lateral surface area of a conical frustum according to the respective parameters which are the radius of the lower base (R), radius of the lower base (r) and the height of the conical frustum.

Now, enter the values appropriately and accordingly for the parameters as required by the **example** above where the** radius of the lower base **is** 22 cm**,** radius of the upper base **is** 19 cm** and **the height** is** 28 cm.**

Finally, Click on Calculate

As you can see from the screenshot above, **Nickzom Calculator** – The Calculator Encyclopedia solves for the** Lateral Surface area of a conical frustum** and presents the formula, workings and steps too.