Percentage

To solve this problem, the user needs to know the formula for compound interest, which is:

A = P(1 + r/n)^(nt)

where: A = the final amount P = the principal amount r = the annual interest rate (as a decimal) n = the number of times the interest is compounded per year t = the number of years

In this problem, the population is increasing by an average of 2% per year, which means the annual interest rate (r) is 2%. The population is not being compounded, so n = 1. The time period (t) is 3 years. We can use this information to solve for the principal amount (P), which is the population in 2000.

Let P be the population in 2000.

Then we have:

2,000,000 = P(1 + 0.02)^3

Simplifying this equation:

2,000,000 = P(1.02)^3

2,000,000 = P(1.061208)

P = 2,000,000/1.061208

P = 1,883,449.599

Rounding this value to the nearest thousand, we get:

The Answer is: A. 1 848 000.

If population doubles every 10 years from 1960 to 1990, that's 30 years = 3 periods. Starting from P, after 3 periods: P × 2^3 = 8P. Percent increase = ((8P - P)/P) × 100 = 700%.

Let original price = 100, consumption = 100, so expenditure = 10000. After 25% price increase, new price = 125. To keep expenditure at 10000: 125 × new consumption = 10000. New consumption = 80, so reduction = 20%. Check: 1.25 × 0.8 = 1 (expenditure unchanged).

Using trick,

Percentage loss in his salary = 35 x 35/100

= 12.25%

For two successive changes of x% and y%, net change = {x + y +xy/100}%

= {- 34 – 35 + (- 34)(- 35)/100}%

=(- 69 + 11.9) % = - 57.1%

So, equivalent discount is 57.1%.

The net annual increase=5% Let the initial population be 100. Then, the population after 2 years =100*1.05*1.05 =110.25 Therefore,% increase in population=110.25-100 =10.25 Thus, this is the correct answer.

Let the number of boys at present = 7x and girls = 8x. After the percentage increment in number of boys and girls we will have:  Number of boys = 7x + 7x*(20/100) = 840x/100 and Number of girls = 8x + 8x*(10/100) = 880x/100 The ratio = (840x/100) : (880x/100) = 21 : 22. So, this is the correct answer.

Let the expenditure and savings be 3x and 2x respectively. Total income = 3x + 2x = 5x Increased income = 5.7x Increased expenditure = 3.3xI Increased savings = 5.7x - 3.3x = 2.4x, i.e. 20% increase So, option (1) is correct.

Money spent on entertainment = 0.5 *(1-1/8) part of the salary. Option (3) is correct.

The percentage of saving Rs. 2400 from her total salary, i.e. Rs. 16000 is calculated by keeping the percentage of savings the same as the amount she would be able to save. Hence, she is able to save Rs. 3000. Now, the amount of money she saves more is Rs. 3000 – Rs. 2400 = Rs. 600. Thus, option (2) is correct.

Correct

Correct options is (2)

Total students = 80 + 60 = 140. Passed in year 1: 60% of 80 = 48. Passed in year 2: 80% of 60 = 48. Total passed = 48 + 48 = 96. Average rate = (96 / 140) * 100 = 960/14 = 480/7 = 68 4/7%.

Let the price of the sugar today be $ 100 $
Then its price tomorrow will be  $ 125 $

So,  to bring back the price to normal it should be decreased $ \cfrac {125-100}{125} \times 100 = 20 \%$

$\Rightarrow$  Here, Approximate Population = $34000-29000=5000$