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Awesome Compound Interest Tricks: Easy Ways with Excel and Calculators!

8

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E

edga

11/10/2025

Maths

Compound Interest

550

11 Oct 2025

1 page

Awesome Compound Interest Tricks: Easy Ways with Excel and Calculators!

E

edga

@edga

Compound interest calculation guide for a 3-year investment using Excel... Show more

23.08.2021

Compound Interest contd

Look out for the question asking only for how
much interest is earned after 3 years?

Chloe places €56.

Calculating Compound Interest for a 3-Year Investment

This page provides a detailed example of how to calculate compound interest for a 3-year investment period. The problem presented involves determining the interest earned on a savings account over three years.

Example: Chloe places €5600 in a savings account at a rate of 4.5% interest per annum. How much interest does Chloe earn after 3 years?

The solution is broken down into clear steps, making it easy to follow the calculation process. First, the annual interest rate is converted to a decimal (1.045) by adding 100% to the given rate of 4.5%. This step is crucial for using the compound interest formula.

Highlight: The compound interest formula used is: Principal × 1+InterestRate1 + Interest Rate^Time

In this case, the calculation is 5600 × 1.045³, which equals €6390.5303. This result is then rounded to €6390.53, representing the total amount after 3 years of compound interest.

Vocabulary: Per annum - Latin for "per year," commonly used in financial contexts to describe annual rates.

To find the interest earned, an important step is highlighted: subtracting the initial principal from the final amount. This gives us €6390.53 - €5600 = €790.53, which is the total interest earned over the 3-year period.

Definition: Compound Interest - Interest calculated on the initial principal and the accumulated interest from previous periods.

This example serves as an excellent demonstration of how to use a compound interest calculator or create one in Excel. It's particularly useful for those learning about monthly compound interest calculators or seeking to understand how compound interest differs from simple interest calculators.

Quote: "Remember this take-away step" - This note emphasizes the importance of subtracting the principal to find the actual interest earned.

By following this example, students can learn to calculate compound interest for various scenarios, such as determining how much interest will be earned on €50,000 in a year or calculating the growth of €15,000 at 15% compounded annually for 5 years. This knowledge is valuable for personal finance, investment planning, and understanding the power of compound interest in long-term savings strategies.



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This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.

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Greenlight Bonnie

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very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.

Rohan U

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I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.

Xander S

iOS user

THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮

Elisha

iOS user

This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now

Paul T

iOS user

The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.

Stefan S

iOS user

This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.

Samantha Klich

Android user

Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.

Anna

iOS user

Best app on earth! no words because it’s too good

Thomas R

iOS user

Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.

Basil

Android user

This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.

David K

iOS user

The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!

Sudenaz Ocak

Android user

In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.

Greenlight Bonnie

Android user

very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.

Rohan U

Android user

I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.

Xander S

iOS user

THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮

Elisha

iOS user

This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now

Paul T

iOS user

 

Maths

550

11 Oct 2025

1 page

Awesome Compound Interest Tricks: Easy Ways with Excel and Calculators!

E

edga

@edga

Compound interest calculation guide for a 3-year investment using Excel and formulas. Learn how to determine interest earned on savings accounts with step-by-step instructions and examples.

• This guide explains how to calculate compound interest for a 3-year investment period.... Show more

23.08.2021

Compound Interest contd

Look out for the question asking only for how
much interest is earned after 3 years?

Chloe places €56.

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Calculating Compound Interest for a 3-Year Investment

This page provides a detailed example of how to calculate compound interest for a 3-year investment period. The problem presented involves determining the interest earned on a savings account over three years.

Example: Chloe places €5600 in a savings account at a rate of 4.5% interest per annum. How much interest does Chloe earn after 3 years?

The solution is broken down into clear steps, making it easy to follow the calculation process. First, the annual interest rate is converted to a decimal (1.045) by adding 100% to the given rate of 4.5%. This step is crucial for using the compound interest formula.

Highlight: The compound interest formula used is: Principal × 1+InterestRate1 + Interest Rate^Time

In this case, the calculation is 5600 × 1.045³, which equals €6390.5303. This result is then rounded to €6390.53, representing the total amount after 3 years of compound interest.

Vocabulary: Per annum - Latin for "per year," commonly used in financial contexts to describe annual rates.

To find the interest earned, an important step is highlighted: subtracting the initial principal from the final amount. This gives us €6390.53 - €5600 = €790.53, which is the total interest earned over the 3-year period.

Definition: Compound Interest - Interest calculated on the initial principal and the accumulated interest from previous periods.

This example serves as an excellent demonstration of how to use a compound interest calculator or create one in Excel. It's particularly useful for those learning about monthly compound interest calculators or seeking to understand how compound interest differs from simple interest calculators.

Quote: "Remember this take-away step" - This note emphasizes the importance of subtracting the principal to find the actual interest earned.

By following this example, students can learn to calculate compound interest for various scenarios, such as determining how much interest will be earned on €50,000 in a year or calculating the growth of €15,000 at 15% compounded annually for 5 years. This knowledge is valuable for personal finance, investment planning, and understanding the power of compound interest in long-term savings strategies.

We thought you’d never ask...

What is the Knowunity AI companion?

Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.

Where can I download the Knowunity app?

You can download the app from Google Play Store and Apple App Store.

Is Knowunity really free of charge?

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Can't find what you're looking for? Explore other subjects.

Students love us — and so will you.

4.9/5

App Store

4.8/5

Google Play

The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.

Stefan S

iOS user

This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.

Samantha Klich

Android user

Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.

Anna

iOS user

Best app on earth! no words because it’s too good

Thomas R

iOS user

Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.

Basil

Android user

This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.

David K

iOS user

The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!

Sudenaz Ocak

Android user

In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.

Greenlight Bonnie

Android user

very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.

Rohan U

Android user

I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.

Xander S

iOS user

THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮

Elisha

iOS user

This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now

Paul T

iOS user

The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.

Stefan S

iOS user

This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.

Samantha Klich

Android user

Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.

Anna

iOS user

Best app on earth! no words because it’s too good

Thomas R

iOS user

Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.

Basil

Android user

This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.

David K

iOS user

The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!

Sudenaz Ocak

Android user

In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.

Greenlight Bonnie

Android user

very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.

Rohan U

Android user

I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.

Xander S

iOS user

THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮

Elisha

iOS user

This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now

Paul T

iOS user