Question
The mean and standard deviation of 6 observations are 10
and 3 respectively. If each observation is multiplied by 4 and then 5 is added to each result, find the new mean and new standard deviation.Solution
If original data has mean μ and SD σ, and we transform x to y = a x + b: New mean = aμ + b New SD = |a| σ Here μ = 10, σ = 3, a = 4, b = 5 New mean = 4×10 + 5 = 45 New SD = 4×3 = 12.
A man wants to invest Rs. 60660 in bank accounts of his two sons whose ages are 12 years and 16 years in such a way that they will get equal amount at a...
- Sohan invested Rs. 11,600 at a simple interest rate of 7.5% per annum for 3.5 years. What will be the total amount he receives after the period?
Rs. 13000 invested for 2 years in a scheme offering compound interest (compounded annually) of 15% p.a. gives an interest that is Rs. 10 less than the i...
Simple interest earned on an amount of Rs. 1000 at rate of R% per annum after 4 years is Rs. 280. Find the simple interest earned on an amount of Rs. 15...
A certain sum is invested at a compound interest rate, compounded annually, which grows to Rs. 12,240 after 2 years and to Rs. 17,625.6 after 4 years. I...
Rs. 6,500 is invested in scheme ‘A’ offering simple interest of 14% p.a. and Rs. 9220 in scheme ‘B’ offering simple interest of 5% p.a. What is ...
A person invested Rs. P on simple interest at the rate of 15% for 5 years, and he invested Rs.(P + 100) at 10% compound interest for 2 years. The total ...
A sum of Rs. 3000 is invested at simple interest for 2 years. If the rate interest for first year is 10% p.a. while 18% p.a. for second year, then find ...
A man deposited Rs. ‘x + 700’ at 12% per annum simple interest and earned Rs. 624 as interest after 2 years. Find the interest earned by him if he d...
Simple interest earned on an amount of Rs.1600 at rate of R% per annum after 4 years is Rs.256. Find the simple interest earned on an amount of Rs.1800 ...
