Question
‘A’ and ‘B’ play a game involving tossing a coin 4
times. ‘A’ wins if exactly two heads appear. Otherwise, ‘B’ wins. Find the probability that ‘A’ wins the game.Solution
Total number of outcomes = 2 4 = 16
Number of favourable outcomes (exactly 2 heads) = C(4,2) = 6
Probability that ‘A’ wins = 6/16 = 3/8
- A person invested Rs. 30,000 in two schemes. One scheme gives a simple interest of 7% p.a., while the other scheme gives 11% p.a. If the total interest ear...
A man invested a certain amount of sum at 12.5% per annum simple interest and earned an interest of Rs.2400 after 4 years. If the same amount is investe...
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 5400 in 3 years and to Rs 6000 in 5 years at simple interest. Find the principal and the rate of interest per annum.
A man invested certain sum at simple interest of r% p.a. such that it amounts to 130% of itself in 3 years. Find the interest earned when Rs. 3000 is in...
- 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...
An amount of 'a' is invested at an annual interest rate of 18% with simple interest, and another amount of 'a + 750' is invested at an annual interest...
A man invested certain sum at 10% p.a. simple interest for his son who was 17 years old. If the amount received by the son when he was 30 years old is R...
Arjun borrowed Rs. 5000 at R% S.I. and Rs. 6000 at (R + 5)% S.I. for 2 years. The total interest paid was Rs. 2800. Find the rate at which he borrowed R...
A sum of Rs. 3200 is invested at simple interest for 2 years. If the rate interest for first year is 12% p.a. while 20% p.a. for second year, then find ...