This discussion is now closed.

Check out other Related discussions

- A level maths binomial distribution question
- S2 binomial distribution question
- Binomial distribution
- A level Maths question
- Negative Binomial Question
- Maths statistics question
- A level further statistics 1 (FS1) edexcel 2024 June 14
- do you always set up binomial probabilities as p(X<=x)?
- Statistics Maths AS- Level help
- Rounding in A-Level Maths
- Cie as level statistics question , please help
- 10 weeks going from C to A* - Alevel
- how to improve in maths a level?
- A level maths binomial expansion question HELP
- WJEC Unit 1 Maths As Level Discussion 15 May 2024
- Binomial expansion
- IAL Mathematics Pure 4 Question:
- How to use Madas Maths
- A level Math
- Edexcel GCSE Statistics Paper 1 Higher Tier (1ST0 1H) - 5th June 2024 [Exam Chat]

1)An archer fires arrows at a target and for each arrow, independently of all the others, the probability that it hits the bull's eye is 1/8.

a)Given that the archer fires 5 arrows, find the probability that fewer than 2 arrows hit the bull's-eye. ans=0.879

The archer fires 5 arrows, collects them from the target and fires all 5 agian.

b) find the probability that on both occasions fewer than 2 hit the bull's eye.

ans=0.773

The archer now fires 60 arrows at a target. using a suitable appoximations find

c)the prob that fewer than 10 hit the bull's eye. ans=0.776

d) the smallest value of m such that the prob that the archer hits the bull-eye with at least m arrows is greater than 0.5. ans= m=7

and i need help with this question...but not sure if its binomial:

2) In joe's roadside cafe, 2/5 of the customers buy a cup of tea.

a) find the prob that at least 4 of the next 10 customers will buy a cup of tea. ans=0.618

a)Given that the archer fires 5 arrows, find the probability that fewer than 2 arrows hit the bull's-eye. ans=0.879

The archer fires 5 arrows, collects them from the target and fires all 5 agian.

b) find the probability that on both occasions fewer than 2 hit the bull's eye.

ans=0.773

The archer now fires 60 arrows at a target. using a suitable appoximations find

c)the prob that fewer than 10 hit the bull's eye. ans=0.776

d) the smallest value of m such that the prob that the archer hits the bull-eye with at least m arrows is greater than 0.5. ans= m=7

and i need help with this question...but not sure if its binomial:

2) In joe's roadside cafe, 2/5 of the customers buy a cup of tea.

a) find the prob that at least 4 of the next 10 customers will buy a cup of tea. ans=0.618

(1)

Let X be the number of hits.

(a)

X ~ Bin(5, 1/8)

P(X < 2)

= P(X = 0) + P(X = 1)

= (7/8)^5 + 5C1 (1/8)(7/8)^4 = 0.879

(b)

[answer to (a)]^2 = 0.773

(c)

X ~ N(60*(1/8), 60*(1/8)(7/8)) = N(7.5, 105/16). Using the continuity correction, the answer is P(X <= 9.5) = Phi((9.5 - 7.5)/sqrt(105/16)) = Phi(0.78072) = 0.783. (This answer doesn't agree with the given one - sorry.)

(d)

X ~ N(7.5, 105/16). Since P(X >= 7.5) = 1/2 and P(X >= 6.5) > 1/2 we have m = 7.

--

(2)

(a) Let N be the number of the next 10 customer who buy a cup of tea. Then N ~ Bin(10, 2/5).

P(N >= 4)

= 1 - P(N = 0) - P(N = 1) - P(N = 2) - P(N = 3)

= 1 - (3/5)^10 - 10C1 (2/5)(3/5)^9 - 10C2 (2/5)^2(3/5)^8 - 10C3 (2/5)^3(3/5)^7

= 0.618

Let X be the number of hits.

(a)

X ~ Bin(5, 1/8)

P(X < 2)

= P(X = 0) + P(X = 1)

= (7/8)^5 + 5C1 (1/8)(7/8)^4 = 0.879

(b)

[answer to (a)]^2 = 0.773

(c)

X ~ N(60*(1/8), 60*(1/8)(7/8)) = N(7.5, 105/16). Using the continuity correction, the answer is P(X <= 9.5) = Phi((9.5 - 7.5)/sqrt(105/16)) = Phi(0.78072) = 0.783. (This answer doesn't agree with the given one - sorry.)

(d)

X ~ N(7.5, 105/16). Since P(X >= 7.5) = 1/2 and P(X >= 6.5) > 1/2 we have m = 7.

--

(2)

(a) Let N be the number of the next 10 customer who buy a cup of tea. Then N ~ Bin(10, 2/5).

P(N >= 4)

= 1 - P(N = 0) - P(N = 1) - P(N = 2) - P(N = 3)

= 1 - (3/5)^10 - 10C1 (2/5)(3/5)^9 - 10C2 (2/5)^2(3/5)^8 - 10C3 (2/5)^3(3/5)^7

= 0.618

- A level maths binomial distribution question
- S2 binomial distribution question
- Binomial distribution
- A level Maths question
- Negative Binomial Question
- Maths statistics question
- A level further statistics 1 (FS1) edexcel 2024 June 14
- do you always set up binomial probabilities as p(X<=x)?
- Statistics Maths AS- Level help
- Rounding in A-Level Maths
- Cie as level statistics question , please help
- 10 weeks going from C to A* - Alevel
- how to improve in maths a level?
- A level maths binomial expansion question HELP
- WJEC Unit 1 Maths As Level Discussion 15 May 2024
- Binomial expansion
- IAL Mathematics Pure 4 Question:
- How to use Madas Maths
- A level Math
- Edexcel GCSE Statistics Paper 1 Higher Tier (1ST0 1H) - 5th June 2024 [Exam Chat]

Latest

Trending