class 10 compound interest pop, dep

CI POP dep

Friday, July 23, 2021 3:05 PM

compound interest is
Rate means
principle means
Time is measures in
For simple interest
SI =

for compound interest
Compound Amount (Yearly)
compound Amount (Half yearly)
Compound Amount (Yearly) if time is given in year and month

Compound Amount (half Yearly) if time is given in year and month

Compound interest (Yearly)

compound interest (Half yearly)
Compound interest (Yearly) if time is given in year and month

Compound Amount (half Yearly) if time is given in year and month

if different rate are given then
Compound Amount (Yearly)

1a) find the compound interest without using formula
P=10000
Rate= 10 %
Time=2 years
for first years ,

Amount for first year
P+ SI=10000+1000=11000
Principal for the second year= Amount of first year=11000

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=1000+1100=2100

1920

a) 2 ) Find the compound interest on Rs 3000 at 10 % for 2 years
Principal= 3000
Rate=10%
Time=2 years
We have,

6300

1) B Find the compound interest on Rs 4000 at 10 % for 3 years

2) Samudra deposits Rs 850 at NBL at the half yearly rate of 8% for 1 year .how much interest will
he get ?
Solution
Principal (P)= 850
Time(T)= 1 years
Rate( R) =8%
CI half yearly=?

4)Jharans got Rs 1881 interest of certain sum for 2 years at 9% compounded yearly . Find the sum
solution
CI=1881
T=2
R=9

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1) In what time the compound amount of Rs 60000 at 10% rate is Rs 79860 ?
Solution
P= 60000
CA=798T0
R=10

T=3
2) Aman lent Rs 5000 in a bank at the rate of 12% p.a for three years
I) HOW MUCH SIMPLE INTEREST WILL BE RECEIVE AFTER 3 YEARS ?
II) ) HOW much CI will he receive after 3 years ?

Solution ,
p=5000
R=12%
T=3

7)Hari borrowed Rs 130000 from krisha at the rate of 21% per annum . At the end of 1 year and 6

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7)Hari borrowed Rs 130000 from krisha at the rate of 21% per annum . At the end of 1 year and 6
month
i) how much simple interest will he has to pay ?
Ii) how much compound interest will he has to pay ?
Solution ,
P=130000
R=21%
T= 1 year 6 month =

1) Find the difference between the compound interest and simple interest on Rs 7500 in 2 years
10% per annum
P=
R=
T=

Now
2) The difference between the compound interest and the simple interest on a sum of money for

two years at interest rate 20% per annum is Rs 400 . Find sum
Solution,
R=20%
T=2
CI-SI=400

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CI-SI=400

10 mohan deposit Rs 5000 at 8% Pa compound interest in a bank . Find the difference between
amount compounded yearly and half yearly in two years.
Solution ,
p= 5000
R=8
T=2
We have,

=849.2928

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Now difference =

1) the sum of simple interest and compound interest after 2 year is Rs 202.5 and the
interest rate is 5% per annum. Find the principal
Solution ,
Time(T) =2 Years
Rate ( R) = 5
CI+SI= 202.50

Now
CI+SI= 202.5
0.1025+0.1P=202.5
0.2025P=202.5
P=1000

12)the simple interest of 2 years is Rs 91 less than its compound interest . If the rate of interest in a

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12)the simple interest of 2 years is Rs 91 less than its compound interest . If the rate of interest in a
year is 15% . Find the sum
SOLUTION ,

Time(T) =2 Years
Rate ( R) = 15
CI+SI= 202.50

Now
CI-SI= 91
0.3225P -0.3P=91
0.0225P=

13) Ram borrowed a sum of money at the rate of 5% simple interest for 2 years and he lent in
compound interest at the same duration of time . In this transaction if he gained Rs 30 find the sum
he borrowed .
Solution,

Time(T) =2 Years
Rate ( R) = 5
CI+SI=30

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Now
CI-SI= 30
0.1025-0.1P=30
0.0025P=30
P=

14) Ram borrowed Rs 4800 from sita at the rate of 10% . At the end of one year
i) How much simple interest will ram have to pay ?
ii) How much compound interest semiannually will Ram have to pay ?
Solution
P=4800
R=10%
T=1year

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=5292
15) The compound interest on a certain sum for 2 year at 10% per annum is Rs 420 .what would be

the simple interest on the same st the same rate for the same time ?
Solution ,
T=2
R=10%
CI=

420
P=

16) According to the system of compound interest , a sum of money in 2 years amounts to Rs 7260
and in 3 years it amounts to Rs 7986. find the rate of interest and sum
Solution ,
CA for 2 years=7260
CA for 3 years=7986
We have ,

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R= 10

FROM EQUATION 1

17) In how many years will Rs 8000 mounts to Rs 13824 at 20% interest compounded annually?
Solution ,
P=
CA=
R=

18) At what rate the compound amount on Rs 576 will be Rs 625 in 2 years ?
P=
CA=
R=

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19) A man deposits a sum of moment at the annual rate of interest 10% and gets the
compound interest of Rs 1986 after 3 years .What was the deposited principle ? What is the
simple interest of the sum for 3 years .
Solution, CI= 1986
Rate= 10%
Time=3 years
We have,

Again

SI=1800

20) Nikkita receive the interest t Rs 254.40 at the end of 2 yers 12% annual compound irate of
interest . If the semiannual compound interest is allowed ,how much more interest will she
receive
Solution ,
CI yearly = 254.40
R=12
T=2

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T=2
We have,

254.40

More amount =
21) The simple interest on a certain sum of money for 2 years at 5% pa is Rs 320 . What will be
the compound interest on the same sum for the same time at the same rate, the interest being
calculated yearly
Solution
T= 2
R=5%
SI=320

22) Bimal deposits Rs 1500 sita finance company and Rs 15000 in Lumbini Finance company at
the rate of 12% per annum. Sita finance company pays interest compounded half yearly and

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the rate of 12% per annum. Sita finance company pays interest compounded half yearly and
Lumbini finance company pays interest compounded yearly . Calculate the interest paid by both
finance companies in 2 years ?
Solution,
P=1500
T=2
R=

23) Compound interest on a sum of money for 2 years compounded annually is Rs 8034. simple
interest on the same sum for the same period an at the same rate is Rs 7800 .find the sum and
rate of interest
SOLUTION ,
CI=8034
SI=7800

again

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From 1
24) The differences between the semi annual compound interested the annul compound
interest on a sum of money for 2 years at the rate o f20% per annum is Rs 482. find the sum
Solution
R=20%
T=2
We have,

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Now difference = 0.4641P-0.44P
482 = 0.4641P-0.44P

set 3 Q
total time 5 years
Rate = 10 %
time for simple interest = 3 years
time for compound interest = 2 years
Final amount = 471900
last 2 years is calculated as compound interest way

471900=P then
p= 39000
for simple interest

p=300000

population
If final population or population after T years is

population after migration in or out or death is

3)The present population of a town is 64000 and it increase at the rate of 5% per annum What will
be the population of the town after two years?
SOLUTION ,
P=64000
T=2
R=5%

=
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4) The population of a town in the year 2012 was 425000. find its population in the years 2014 if
the rate of annual increaser is 4% per year
Solution
P=42500( initial population i.,te 2012)
R= 4%
T= 2 ie (2014 -2012)

5) Two years ago the population of a village was 15000 and the rate of growth of pollution is 4% .
What is the present population of the village?
SOLUTION
P=1500
R=
T=

6) The present population of nagarkot is 48400. the annual growth rate is 10% . What was the
population of Nagarkot before 2 years?
SOLUTION,
P=
R=
T=

7) The population of a village was 200. if 5% of the population was migrated in and 2% died due to different causes within a yea r .what would be the population of the village after
a year?
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P=
R=
T=

8) The present population of ghandruk village is 13310 and rate of growth is 10% how many years ago the population was 10000?

P=
R=
T=

9) One years ago the population of a village was 10000. the population at present is 10210? Find
the population growth rate ?
SOLUTION
P=
R=
T=

10) The population of Dhading Bensi increase 10% ever year . If the present population id 60000. Find its population after 2 years and before two years
Solution

P=
R=
T=

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11) The population of village increase every year by 5%. At the send of two years ,the total
population of the village was 10000. if 1025 were migrated to other places what was the
population of the village in the beginning ?
Solution ,
P=
R=
T=

12) The population of Kathmandu valley was 1000000 in the year 2057 and the population growth
rate was 4.5% . If 25000 men migrated here from other places in the year 2058 BS what will be
the total population in the year 2060 ?
Solution ,
Population in 2057=1000000
R=4.5%
Population in 2058(after 1year before migration) =

Population in 2058(after 1year before migration) =
Population in 2060 ( after 2 years) =

13) Two years ago , the population of a village was 5000 . During the first year ,it increased by 7% but
due to an epidemic , it decreased by 6% in the following year . What is the population of the
village now ?
Solution,
P=

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P=
R= 7-6
T=

14) the population of a village 2 years ago was 31250 . The population growth rate of the town is
6% . One year ago 625 people migrated in the village . Find the present population
Solution
P=
R=
T=

15) The growth of curd clotting bacteria is 5% per hour . If the number of bacteria in the 7 pm evening is 1.012 , what wasthe number beforre 4 hours ? Find it
Solution

P=

R=
T=

16) T the present population of a city is 200000. if the population of the city increased first year by
2% then 4% and 5% respectively in continued 3 years . What will be the population city after 3
years ?
Solution ,
P=200000

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T= 3 years

Deprecation

If final Price price after T years is then

1 ) The present price of a motor cycle is Rs 140000 . If it depreciated at 7% per year , what will be the price of the motorc ycle after 2 year?
Solution ,

P=
R=
T=

2) the value of a machine depreciates at the rate of 20% pa compound depreciation . Find the total compound depreciation after 3 years if the present value is Rs 175000.
Solution

P=
R=
T=

3) A scooter which is supposed to depreciate at the rate of 15% per year was sold at Rs 72250 after a year . At what price was i t bought ?

P=
R=
T=

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4 ) The value of an article is depreciated from Rs 18000 to Rs 14580 in two year , find the rate of depreciation

P=
R=
T=

The value of house constructed at a cost of Rs 204800 is depreciating g at the rate of 12.5% .when will be the value of the h ouse Rs 156800?

P=
R=
T=

6) A new car cost Rs 3600000 its price depreciation at there after 10% a year during the first two years and 20% a year the re after . What will be the price of the car after 3
year?

7) A company declared to cut off its 10% worker evert year due the low demand int
market .there are 5832 workers recently working the company . How many workers were there
in the company before 3 years?
P=
R=
T=

8) the share value of finance company depreciates by 10% continually until 2 years so that januka
sold some shares at Rs 48660 .how many share of Rs 100 were sold by her?
P=?
R= 10%
T= 2

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9) 3 years ago Bharat bought 5 ropani of land at Rs 28000. due to t due political instability of the country the price of the la nd is depreciated . If the price of the land id

depreciated 5% what is the price of the land per ropani

P=
R=
T=

10) Furba bought a tractor at Rs 720000. he earned Rs 220000 in 3 years from this and sold it a price which is depreciate
rate of 10% What sis his profit or loss . find it .

P=72000
R= 10
T= 3

In a community jungle there are 20000 tall tree .due to energy scarcity , the consumers cut down 8% tree how many tree are cu t in 2 years ? Can you find the alternative ways
to solve

P=
R=
T=

11 present price of a machine is 200000. if the price of the machine depreciates first year by 2%
then 4% and 5% respectively in continued 3 years . What will be the population city after 3
years ?
P=
R=

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R=
T=

Due to the use of medicine the number of bacteria decreasing at rate of 20 % per day so that the

number of bacteria after 4 days in what was the number of bacteria before 4 days ?

P=

R=
T=

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