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Maths year 11

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Original post by z_o_e
Did the second bit

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That's right.
Reply 981
Original post by RDKGames
That's right.


Yaaaye thanks.

I'll do this now
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Reply 982
Original post by RDKGames
That's right.


Can you do the first one as an example please?


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Reply 984
Original post by RDKGames
That's right.


I don't know what bounds arw

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This is simple interest. This means that the interest back does not stack on previous figures, it only goes off the initial one all the time.

Q1:

8% = 0.08

Per annum means per year, and there are 12 months in a year. If the interest is 8% per year, then covert this into a decimal, and divide it by 12 to find out how much it is per month. 0.08/12 = 8/1200 = 2/300. We can convert this back into a percentage but there is no need as we don't need to use that percentage in our calculation. Now we can multiply this by 8 and get yourselves the amount for 8 months. This would be 8*(2/300) which is 16/300.

Now then;

To find the simple interest, you take the initial amount (720)
and now multiply it by the interest over these 8 months, which we found to be 16/300 as a fraction.

720*(16/300) = 38.4

Therefore the answer is £38.40.
Original post by z_o_e
I don't know what bounds arw

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First have a go at the simple interest stuff. I've explained it in the post above for the first question.
Reply 987
Original post by RDKGames
First have a go at the simple interest stuff. I've explained it in the post above for the first question.


I don't understand this bit.

As I got 0.666 something recurring.
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Original post by z_o_e
I don't understand this bit.

As I got 0.666 something recurring.
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You should really stop throwing the equals sign around so much.

0.08 is the interest per year (makes sense as it's 8%) so by dividing it by 12 you are finding the interest per month. 12 months in a year hence the reason for the 12. Rather than writing it as 0.666 recurring, you can leave it as a fraction.
Reply 989
Original post by RDKGames
You should really stop throwing the equals sign around so much.

0.08 is the interest per year (makes sense as it's 8%) so by dividing it by 12 you are finding the interest per month. 12 months in a year hence the reason for the 12. Rather than writing it as 0.666 recurring, you can leave it as a fraction.


But I didn't get that


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Original post by z_o_e
But I didn't get that


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That's because it's not 0.6666...!

DON'T convert this into a decimal otherwise you'd end up with 0.08/12 again when you attempt to convert it into a fraction! You'd be doing a pointless cycle. Just simplify this fraction. Multiply the top and bottom by 100 then simplify it down: 0.08/12 = 8/1200 = 2/300
(edited 7 years ago)
Reply 991
Original post by RDKGames
This is simple interest. This means that the interest back does not stack on previous figures, it only goes off the initial one all the time.

Q1:

8% = 0.08

Per annum means per year, and there are 12 months in a year. If the interest is 8% per year, then covert this into a decimal, and divide it by 12 to find out how much it is per month. 0.08/12 = 8/1200 = 2/300. We can convert this back into a percentage but there is no need as we don't need to use that percentage in our calculation. Now we can multiply this by 8 and get yourselves the amount for 8 months. This would be 8*(2/300) which is 16/300.

Now then;

To find the simple interest, you take the initial amount (720)
and now multiply it by the interest over these 8 months, which we found to be 16/300 as a fraction.

720*(16/300) = 38.4

Therefore the answer is £38.40.


I got 4/75 :frown:


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That's good! But that's the interest percentage over 8 months. Now multiply the initial investment by this fraction :smile:
Reply 993
Original post by RDKGames
That's good! But that's the interest percentage over 8 months. Now multiply the initial investment by this fraction :smile:




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Reply 994
Original post by RDKGames
That's good! But that's the interest percentage over 8 months. Now multiply the initial investment by this fraction :smile:


I started this one off



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Original post by z_o_e
I started this one off



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Good. You found the interest per month there. Carry on. :smile:
Reply 996
Original post by RDKGames
Good. You found the interest per month there. Carry on. :smile:




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Correct. Though uhh... you said that 0.12/12=1/100 then on the next line you proceeded to work out 3/300 through manipulation? Why? You know that 3/300=1/100 right? :tongue:

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