1. A coin is tossed 100 times. Heads appear 56 times. What is the experimental probability of getting a head?
- A0.56
- B0.44
- C0.50
- D0.64
Show answer
Answer: A) 0.56
Experimental probability = favourable trials / total trials = = 0.56.
Class 9 Experimental Probability — practice questions with answers
Statistics · 5 sample questions from the school syllabus. Try each one, then open the answer and the worked solution.
2. Out of 400 cricket balls inspected, the experimental probability of a defective ball is 0.05. How many were defective?
- A20
- B40
- C22
- D18
Show answer
Answer: A) 20
Defective = 0.05 x 400 = 20.
3. The marks of 50 students were recorded. 35 scored above 60%. The experimental probability that a randomly chosen student scored 60% or below is:
- A0.3
- B0.7
- C0.35
- D0.65
Show answer
Answer: A) 0.3
60% or below = 50 - 35 = 15. P = = 0.3.
4. In a school of 1500 students, a survey found the experimental probability that a student walks to school is 0.28 and the probability that a student comes by bus is 0.46.
How many students use some OTHER mode of transport?
How many students use some OTHER mode of transport?
- A390
- B350
- C780
- D430
Show answer
Answer: A) 390
Other = 1 - 0.28 - 0.46 = 0.26. Number = 0.26 x 1500 = 390.
5. In an experiment a die was rolled N times. The experimental probabilities recorded were:
P(1) = 0.16, P(2) = 0.18, P(3) = 0.14, P(4) = 0.20, P(5) = 0.15.
The number 6 came up 51 times.
Find P(6) and then the total number of rolls N.
P(1) = 0.16, P(2) = 0.18, P(3) = 0.14, P(4) = 0.20, P(5) = 0.15.
The number 6 came up 51 times.
Find P(6) and then the total number of rolls N.
- AP(6) = 0.17, N = 300
- BP(6) = 0.17, N = 51
- CP(6) = 0.16, N = 300
- DP(6) = 0.18, N = 283
Show answer
Answer: A) P(6) = 0.17, N = 300
P(6) = 1 - (0.16+0.18+0.14+0.20+0.15) = 1 - 0.83 = 0.17. Since 51 rolls correspond to P = 0.17, N = = 300.
Practise all 50 questions free →
10 free questions a day without an account — unlimited with a free account.