唔該給以下題目的列式,步驟和答案,THX
1. Raymond deposits $120000 in a bank at an interest rate of 12% p.a. Find the simple interest received after 6 years.
2. Find the amount if $342000 is deposited in a bank at an interest rate of 5% p.a. simple interest for 8 months.
3. If Lawrence deposits $50000 in a bank at an interest rate of 3% p.a. simple interest for 3.5 years, what is the amount he will finally get?
4. Cherry borrows a sum of money form a bank at an interest rate of 5.5% p.a. If she has to pay $3300 simple interest after 2 years, find the amount of money she borrows.
5. Simple interest is given at an interest rate of 3.6% p.a. for an investment of $40000. How long will it take for the amount to be come $43600?
6. Suki deposits $8000 in a bank where simple interest is calculated. If she will get the amount $8360 after 9 months, what is the interest rate per annum?
英文數學(Simple Interest)
2013-11-26 5:04 am
回答 (3)
2013-11-26 6:33 am
✔ 最佳答案
1.Simple interest received after 6 years
= $120000 x (1 + 12% x 6)
= $120000 x 1.72
= $206400
=====
2.
Amount for 8 month
= $342000 x [1 + 5% x (8/12)]
= $342000 x (31/30)
= $353400
=====
3.
Amount he will finally get
= $50000 (1 + 3% x 3.5)
= $50000 x 1.105
= $55250
=====
4.
Amount of money she borrows
= $3300 ÷ (5.5% x 2)
= $3300 ÷ 0.11
= $30000
=====
5.
Time taken
= (43600 - 40000) ÷ 40000 ÷ 3.6% years
= 3600 ÷ 40000 ÷ 3.6% years
= 0.09 ÷ 3.6% years
= 2.5 years
=====
6.
Interest rate per annum
= [(8360 - 8000) ÷ 8000 ÷ (9/12)] x 100%
= [360 ÷ 8000 ÷ (9/12)] x 100%
= [(360/8000) x (12/9)] x 100%
= 0.06 x 100%
= 6%
2013-11-25 22:36:11 補充：
4. Alternative method :
Let $P the amount she borrows.
P x 5.5% x 2 = 3300
0.11P = 3300
P = 30000
Hence, the amount she borrows is $30000.
2013-11-25 22:39:29 補充：
5. Alternative method :
Let t years be the time taken.
40000 x (1 + 3.6% x t) = 43600
40000 + 1440t = 43600
1440t = 3600
t = 2.5
Hence, time taken = 2.5 years
2013-11-25 22:42:13 補充：
6. Alternative method :
Let R% be the interest rate.
8000 x [1 + R% x (9/12)] = 8360
8000 + 60R = 8360
60R = 360
R = 6
Hence, interest rate = 6%
參考: andrew, andrew
2013-11-28 10:24 pm
1.
The simple interest received after 6 years
= 120000 x 12% x 6
= 14400 x 6
= $86400
2.
The amount for 8 months
= 342000 x 5% x 8/12 + 342000
= 17100 x 8/12 + 342000
= 11400 + 342000
= $353400
3.
The amount he will finally get
= 50000 + 50000 x 5% x 3.5
= 50000 + 2500 x 3.5
= 50000 + 8750
= $58750
4.
let $p be the principal.
p x 5.5% x 2 = 3300
2p = 60000
p = 30000
∴ The principal is $30000.
5.
let t years be the period.
40000 x 3.6% x t = 43600 - 40000
1440t = 3600
t = 2.5
∴ It takes 2.5 years.
6.
let r% be the interest rate per annum
8000 x r% x 9/12 = 8360 - 8000
6000 x r% = 360
r % = 0.06
r = 6
∴ The interest rate per annum is 6%.
2013-11-28 14:29:36 補充：
Sorry!
有一點錯誤要修正
4.
let $p be the principal.
p x 5.5% x 2 = 3300
2p = 60000
p = 30000
∴ The principal is $30000.
Amount of money he borrows
= 30000 + 3300
= $33300
The simple interest received after 6 years
= 120000 x 12% x 6
= 14400 x 6
= $86400
2.
The amount for 8 months
= 342000 x 5% x 8/12 + 342000
= 17100 x 8/12 + 342000
= 11400 + 342000
= $353400
3.
The amount he will finally get
= 50000 + 50000 x 5% x 3.5
= 50000 + 2500 x 3.5
= 50000 + 8750
= $58750
4.
let $p be the principal.
p x 5.5% x 2 = 3300
2p = 60000
p = 30000
∴ The principal is $30000.
5.
let t years be the period.
40000 x 3.6% x t = 43600 - 40000
1440t = 3600
t = 2.5
∴ It takes 2.5 years.
6.
let r% be the interest rate per annum
8000 x r% x 9/12 = 8360 - 8000
6000 x r% = 360
r % = 0.06
r = 6
∴ The interest rate per annum is 6%.
2013-11-28 14:29:36 補充：
Sorry!
有一點錯誤要修正
4.
let $p be the principal.
p x 5.5% x 2 = 3300
2p = 60000
p = 30000
∴ The principal is $30000.
Amount of money he borrows
= 30000 + 3300
= $33300
2013-11-26 6:38 am
1. interest=120000*12%*6
=$86400
2. amount=342000(1+5%*8/12)
=$353400
3. amount=50000(1+3%*3.5)
=$55250
2013-11-25 22:38:10 補充：
4. let x be the amount.
x*5.5%*2=3300
x=30000
amount=$30000
5. let n be the years.
40000(1+3.6%*n)=43600
n=2.5
it will take the amount after 2.5 years.
6. let r% be the interest rate.
8000(1+r%*9/12)=8360
r=6
the interest rate is 6%.
=$86400
2. amount=342000(1+5%*8/12)
=$353400
3. amount=50000(1+3%*3.5)
=$55250
2013-11-25 22:38:10 補充：
4. let x be the amount.
x*5.5%*2=3300
x=30000
amount=$30000
5. let n be the years.
40000(1+3.6%*n)=43600
n=2.5
it will take the amount after 2.5 years.
6. let r% be the interest rate.
8000(1+r%*9/12)=8360
r=6
the interest rate is 6%.
收錄日期: 2021-04-13 19:51:16
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20131125000051KK00177