Question
A boat can travel 22 km more in downstream than that in
upstream, in 11 hours while the difference between the time taken by the same boat to travel 220 km and 120 km, in still water, is 4 hours. Find the approximate time taken by the boat to travel 200 km in downstream and 110 km in upstream.Solution
Let the speed of boat in still water and speed of stream be 'x' km/hr and 'y' km/hr, respectively. According to question; (220/x) - (120/x) = 4 Or, (100/x) = 4 So, x = 25 Now, 11 x (25 + y) = 11 x (22 - y) + 22 Or, 275 + 11y = 275 - 11y + 22 Or, 22y = 22 So, y = 1 So, downstream speed of the boat = (25 + 1) = 26 km/hr And, upstream speed of the boat = (25 - 1) = 24 km/hr Required time taken = (200/26) + (110/24) ~ (8 + 5) ~ 14 hours
Azhar deposited an amount of Rs. 'x + 250' in a simple interest scheme at a rate of 20% per annum for a duration of 3 years. Additionally, he invested R...
Simple interest received at the rate of 15% p.a. for 2 years on a principal amount of Rs. 9000 is twice of the simple interest received at 10% p.a. for ...
A sum of money amounts to Rs. 5600 in 5 years at 8% simple interest per annum. Find the principal and the interest earned.
A man deposited Rs. 16000 at 10% compound interest, compounded annually while Rs. 14000 at 13% simple interest per annum. What will be the difference be...
An individual invested an amount of money in a financial scheme that accrues compound interest at an annual rate of 30%, compounded yearly. After 2 year...
What sum of money must be given at simple interest for 8 months at 3% per annum in order to earn Rs. 260 interest?
A sum of ₹12,000 is invested at 8% per annum simple interest for 3 years. What will be the interest  earned?
A man invested a certain amount of sum at 12.5% per annum simple interest and earned an interest of Rs.2700 after 4 years. If the same amount is investe...
- An amount was invested at a simple interest rate. After 6 years, it amounted to (126/108) times the amount it had reached in 4 years. What is the rate of i...
- A sum of Rs. 1,500 is invested at a simple interest rate of 10% per annum for 18 months. If the interest earned is Rs. 'q', find the value of (q - 15).