An amount of Rs. 20,000 was invested in Company 'B' in 2008 and after one year the entire amount along with interest was will be reinvested in the Company A for one more year. What will be total amount of interest accrued?

We can apply the formula to calculate the interest amount
I = P x R x t where
A = Total Accrued Amount (principal + interest)
P = Principal Amount
I = Interest Amount
R = Rate of Interest per year as a percent;
t = Time Period involved in years

For Company A in 2006,
Principle amount = 10000
Rate of interest = 11.5 % ( As per given graph for company A in 2006)
Time = 1 year
The interest amount received by Samir in 2007 I = P x R x t
The interest amount received by Samir in 2007 = 10000 x 11.5 x 1/100= 10000 x 115 x 1/10 x 100 = 10 x 115 = 1150
Total amount received by Samir in 2007 = Interest amount + Principal amount = 10000 + 1150 = 11150
Again For Company A in 2007,
Principle amount = 11150
Rate of interest = 15 % ( As per given graph for company A in 2007)
Time = 1 year
The interest amount received by Samir in 2008 I = P x R x t
The interest amount received by Samir in 2008 = 11150 x 15 x 1/100 = 1115 x 15/10 = 1115 x 3/2 = 3345/2 = 1672.5
Total amount received by Samir in 2008 = Interest amount + Principal amount = 11150+ 1672.5 = 12822.50
Hence, their interest = 12822.50 - 10000 = 2822.50
For Company B in 2006,
Principle amount = 10000
Rate of interest = 13.5 % ( As per given graph for company B in 2006)
Time = 1 year
The interest amount received by Samir in 2007 I = P x R x t
The interest amount received by Samir in 2007 = 10000 x 13.5 x 1/100= 10000 x 135 x 1/10 x 100 = 10 x 135 = 1350
Total amount received by Samir in 2007 = Interest amount + Principal amount = 10000 + 1350 = 11350
Again For Company B in 2007,
Principle amount = 11350
Rate of interest = 14 % ( As per given graph for company B in 2007)
Time = 1 year
The interest amount received by Samir in 2008 I = P x R x t
The interest amount received by Samir in 2008 = 11350 x 14 x 1/100 = 1135 x 14/10 = 1135 x 7/5 = 227 x 7 = 1589
Total amount received by Samir in 2008 = Interest amount + Principal amount = 11350+ 1589 = 12939
Since, their interest = 12939 - 10000 = Rs. 2939
Hence, difference between the interests earned = 2939 - 2822.50 = Rs. 116.50
If Samir had invested the amount in company B for both years then he would get Rs. 116.50 more.

Simple interest formula I = P x R x T where
P is the Principal amount of money to be invested at an Interest Rate R% per period for T Number of Time Periods.

Interests accrued by Saurabh in 2007 from company A = 12000 x 15 x 1/100
Interests accrued by Saurabh in 2007 from company B = 15000 x 14 x 1/100
Total interests accrued by Saurabh in 2007 from company A and company B = ( 12000 x 15 x 1/100 ) + (15000 x 14 x 1/100 )
Total interests accrued by Saurabh in 2007 from company A and company B = ( 120 x 15 ) + (150 x 14 )
Total interests accrued by Saurabh in 2007 from company A and company B = 1800 + 2100
Total interests accrued by Saurabh in 2007 from company A and company B = Rs. 3900

Simple interest formula I = P x R x T where
P is the Principal amount of money to be invested at an Interest Rate R% per period for T Number of Time Periods.

Interests earned by Gopal from Company A in 2003 = 25000 x 12 x 1/100
Interests earned by Gopal from Company A in 2003 = 250 x 12 = 3000
Total amount in the end of year 2003 = 25000 + 3000 = 28000
Interests earned by Gopal from Company B in 2004 = 28000 x 14 x 1/100
Interests earned by Gopal from Company B in 2004 = 280 x 14
Interests earned by Gopal from Company B in 2004 = 3920
Total interests accrued by Gopal in 2003 and 2004 from company A and company B = 3000 + 3920
Total interests accrued by Gopal in 2003 and 2004 from company A and company B = Rs. 6920

Average profit made by company A in all the years = Rs. (3 + 5 + 4 + 5 + 6 + 6)lakhs/6
= Rs. 29 /6 ? Rs. 4.83 lakh = Rs. 4,83,000

Expenditure of Company B in 2008 = Rs. 22,11,430 and their profit = Rs. 4,00,000
Since, Income = 22,11,430 + 4,00,000 = Rs. 26,11,630

Compound interest = P(1 + r)^t - P
or Compound interest = P[(1 + r)^t - 1]
where P = the principal investment amount (the initial deposit or loan amount)
r = the annual interest rate
t = the number of years the money is invested or borrowed for.
Required amount of interest earned by Madhava in 2007 = 15000[(1+ 15/100)² - 1]
= 15000[(115/100)² - 1]
= 15000[(23/20)² - 1]
= 15000[(23 x 23 /20 x 20) - 1]
= 15000[ (529/400) - 1]
= 15000[(529 - 400)/400]
= 15000 x 129/400
= 19350/4
= Rs. 4837.50

From above given graph we can see that there are two months for which graph is going Up.
By seeing the graph we can see that graph is going up for the month of May and June.
So required answer will be May and June only.

Average percentage increase of the commodities
Hence , Required answer will be January.

From above graph ,
Since , In July and August months did all the commodities show decline or no increase from the previous months.
Required answer will be July and August only .