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Percentages and compound interest

Harry invests £6000 into a savings account
The account pays 3.4% compound interest

What is his investment after 3 years, give your answer to the nearest penny
Original post by Faiza.ii
Harry invests £6000 into a savings account
The account pays 3.4% compound interest

What is his investment after 3 years, give your answer to the nearest penny


What have you been able to do so far? What are your thoughts on what to do?
Reply 2
Original post by Y11_Maths
What have you been able to do so far? What are your thoughts on what to do?


I’m not exactly sure as this is a new topic we are doing and my teacher just sent me these random questions xx
Original post by Faiza.ii
I’m not exactly sure as this is a new topic we are doing and my teacher just sent me these random questions xx


Ok well when you increase something by a percent you are wanting 100% of your original value plus the added % you want. So in this instance you are adding 3.4% to 100% so we have 103.4. This means our multiplier will be 1.034. It is wanting us to find his investment after 3 years to this will be how many times we multiply it (we can also write it as to the power of 3). So your calculation will be 6000(original investment) multiplied by 1.034(percentage increase) to the power 3(hence 3 years)

So it will look like this on your calculator:
6000*1.034^3
Then round it as it says so in the question :smile:
Reply 4
Original post by Y11_Maths
Ok well when you increase something by a percent you are wanting 100% of your original value plus the added % you want. So in this instance you are adding 3.4% to 100% so we have 103.4. This means our multiplier will be 1.034. It is wanting us to find his investment after 3 years to this will be how many times we multiply it (we can also write it as to the power of 3). So your calculation will be 6000(original investment) multiplied by 1.034(percentage increase) to the power 3(hence 3 years)

So it will look like this on your calculator:
6000*1.034^3
Then round it as it says so in the question :smile:


Thank you so much xx
Original post by Faiza.ii
Thank you so much xx


Welcome
Reply 6
yeah but whats the answer
Original post by neysa80
yeah but whats the answer

the methodology is the important bit, but feel free to just plug the numbers into a calculator in if your curious...

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