## O-Level Elementary Math

- onceuponachild2008
- KiasuNewbie
**Posts:**8**Joined:**Tue Aug 23,**Total Likes:**1

### Re: O-Level Elementary Math

Hi, can someone help me with this question on compound interest?

A sum of money is interested at 7% per annum compound interest.

Find the minimum number of years that the sum of money has to be

invested for the accumulated interest to be more that twice the initial sum of money.

Thanks in advance

A sum of money is interested at 7% per annum compound interest.

Find the minimum number of years that the sum of money has to be

invested for the accumulated interest to be more that twice the initial sum of money.

Thanks in advance

### Re: O-Level Elementary Math

onceuponachild2008 wrote:Hi, can someone help me with this question on compound interest?

A sum of money is interested at 7% per annum compound interest.

Find the minimum number of years that the sum of money has to be

invested for the accumulated interest to be more that twice the initial sum of money.

Thanks in advance

### Re: O-Level Elementary Math

Can someone help me with these questions?

1) Kumar borrowed $1800. He had to repay $1989 after 9 months, including the simple interest charged to him. Find the interest rate of the loan.

2) Meiyi deposited $7200 in her savings account which earns interest at the rate of 5% per annum. The money is deposited for 4 years.

a) Calculate the interest earned if the interest is

-Simple interest,

-Compounded annually.

b) Find the difference between the compound interest ans simple interest in (a).

3) A loan grows to $3740 after 1 year and $4114 after 2 years with compound interest which is compited annually. Find

a) the interest rate per annum,

b) the original loan.

4) A sum of money grows to $3800 in 3 years at 6% per annum compound interest. Find the sum of

money if the interest is compounded

a) yearly,

b) monthly.

Thanks

1) Kumar borrowed $1800. He had to repay $1989 after 9 months, including the simple interest charged to him. Find the interest rate of the loan.

2) Meiyi deposited $7200 in her savings account which earns interest at the rate of 5% per annum. The money is deposited for 4 years.

a) Calculate the interest earned if the interest is

-Simple interest,

-Compounded annually.

b) Find the difference between the compound interest ans simple interest in (a).

3) A loan grows to $3740 after 1 year and $4114 after 2 years with compound interest which is compited annually. Find

a) the interest rate per annum,

b) the original loan.

4) A sum of money grows to $3800 in 3 years at 6% per annum compound interest. Find the sum of

money if the interest is compounded

a) yearly,

b) monthly.

Thanks

- kennethTutor
- OrangeBelt
**Posts:**39**Joined:**Mon Jul 13,**Total Likes:**2

### Re: O-Level Elementary Math

For Q1, we can apply the simple interest formula. Solution: http://imgur.com/72xfOSnBeikiasu wrote:Can someone help me with these questions?

1) Kumar borrowed $1800. He had to repay $1989 after 9 months, including the simple interest charged to him. Find the interest rate of the loan.

2) Meiyi deposited $7200 in her savings account which earns interest at the rate of 5% per annum. The money is deposited for 4 years.

a) Calculate the interest earned if the interest is

-Simple interest,

-Compounded annually.

b) Find the difference between the compound interest ans simple interest in (a).

3) A loan grows to $3740 after 1 year and $4114 after 2 years with compound interest which is compited annually. Find

a) the interest rate per annum,

b) the original loan.

4) A sum of money grows to $3800 in 3 years at 6% per annum compound interest. Find the sum of

money if the interest is compounded

a) yearly,

b) monthly.

Thanks

For Q2, we apply the simple interest formula for the simple interest portion. Next, we have to apply the compound interest formula. Solution: http://imgur.com/tqqPdlc

For Q3, we have to form two equations using the information provided by the question. After that, we solve the equations like how we solve simultaneous equations. Solution: http://imgur.com/T5atXo5

For Q4, we use the compound formula, but we have to change R and n, as the time period in which interest is compounded is different.

**Pay attention to this type of problem.**

Solution: http://imgur.com/TZWCGEb

- questionable_i
- BrownBelt
**Posts:**535**Joined:**Sat Oct 10,**Total Likes:**1

### Re: O-Level Elementary Math

Hi, can someone help me with this question on compound interest?

Mr Chua borrows a sum of money from the bank which charges a compound interest of 4.2% per annum, compounded quarterly. Given that Mr Chua had to pay $96.60 in interest payments at the end of the first year, find the original sum of money borrowed, giving your answer correct to the nearest cent.

Mr Chua borrows a sum of money from the bank which charges a compound interest of 4.2% per annum, compounded quarterly. Given that Mr Chua had to pay $96.60 in interest payments at the end of the first year, find the original sum of money borrowed, giving your answer correct to the nearest cent.

- kennethTutor
- OrangeBelt
**Posts:**39**Joined:**Mon Jul 13,**Total Likes:**2

### Re: O-Level Elementary Math

We apply the compound interest formula. In this case, since we do not know what is the principal amount, we can use algebra to solve this problem. Remember,questionable_i wrote:Hi, can someone help me with this question on compound interest?

Mr Chua borrows a sum of money from the bank which charges a compound interest of 4.2% per annum, compounded quarterly. Given that Mr Chua had to pay $96.60 in interest payments at the end of the first year, find the original sum of money borrowed, giving your answer correct to the nearest cent.

Total amount (A) = Principle + Interest

Solution: http://imgur.com/VgSVC86

- questionable_i
- BrownBelt
**Posts:**535**Joined:**Sat Oct 10,**Total Likes:**1

### Re: O-Level Elementary Math

but where does the come from?kennethTutor wrote:We apply the compound interest formula. In this case, since we do not know what is the principal amount, we can use algebra to solve this problem. Remember,questionable_i wrote:Hi, can someone help me with this question on compound interest?

Mr Chua borrows a sum of money from the bank which charges a compound interest of 4.2% per annum, compounded quarterly. Given that Mr Chua had to pay $96.60 in interest payments at the end of the first year, find the original sum of money borrowed, giving your answer correct to the nearest cent.

Total amount (A) = Principle + Interest

Solution: http://imgur.com/VgSVC86

- kennethTutor
- OrangeBelt
**Posts:**39**Joined:**Mon Jul 13,**Total Likes:**2

### Re: O-Level Elementary Math

questionable_i wrote:but where does the come from?

From the fourth line from the last:

P + 96.6 = P (1.042666)

P + 96.6 = 1.042666 P

Now we solve the equation for P:

1.042666 P - P = 96.6

0.042666 P = 96.6

P = 2264.09307 = $2264.09

- RedAngryBird
- KiasuNewbie
**Posts:**1**Joined:**Tue Mar 22,

### Re: O-Level Elementary Math

PLS HELP IN THIS QUESTION!!!!!

The Probability that Lisa and Meiling will pass a driving test are 2/3 and 3/8 respectively. Find the probability that

a)both Lisa and Meiling will pass the test.

b)only one of them will pass the test.

The Probability that Lisa and Meiling will pass a driving test are 2/3 and 3/8 respectively. Find the probability that

a)both Lisa and Meiling will pass the test.

b)only one of them will pass the test.