# Mary takes a loan of $12000 to buy a car. This loan is consolidated with her current home loan at 7.9%p.a over a 15 years term, calculated monthly with monthly repayments. Calculate the increase...

Mary takes a loan of $12000 to buy a car. This loan is consolidated with her current home loan at 7.9%p.a over a 15 years term, calculated monthly with monthly repayments.

Calculate the increase in home loan monthly repayments and the total interest charged over 15 years.

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Only saw your request today. My apologies for not replying sooner. Please post your question separately with attachments (they did not post on this one). The subject should be Science rather than Math. Thank you.

As we know how much Mary needs **now**, we can use the 'Present Value Formula' to calculate:

`P=(x[1-(1+i)^-n])/i`

where P=$12 000 n=15 years x 12 (compounded monthly) and

i=7.9% which is `0.079/12` also because of compound interest

`therefore 12 000 =(x[1-(1+(0.079/12))^-(15 times 12)])/(0.079/12)`

`therefore 12 000 times (0.079/12) = x[1-(1.306935881)^(-180)]`

`therefore (12 000 times 0.079/12)/(1-(1.306935881)^-180)=x` (Care not to round off too soon)

`therefore x=$79.00`

If Mary is paying $79 extra per month for 15 years (180 months) she will pay $14 220 - $12 000 in interest = $2220

**Ans: Mary's home loan will increase by $79,00 per month and interest will amount to $2220**

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Hi durbanville, I was just wondering would you be able to help me with this question? thanks

“The second harmonic adds clearness and brilliance but nothing else,…The octave can introduce no difference of timbre.

The third harmonic again adds a certain amount of brilliance because of its high pitch, but it also introduces a difference of timbre.” (Jeans, J. 1938 *Science & Music*, Cambridge University Press, London)

If **only one harmonic** is combined with the fundamental, investigate Jeans’ claim.

we know that the fundamental tone is y=0.3sin(80*pi*x) (therefore 2nd --> 0.3sin(160*pi*x), 3rd--> 0.3sin(240*pi*x) etc )

I have attached some graphs that I graphed (fund+2nd har, fund+3rd har etc). when you are answering the question could you please make sure you refer to the graph that I have given. hope that makes sense, let me know if you need anymore info,

thanks :)