The minimum number of times one has to toss a fair coin so that the probability of observation at least one head is at least 90% is :

  • Option 1)

    5

  • Option 2)

    3

  • Option 3)

    4

  • Option 4)

    2

 

Answers (1)

Let x fair coin tossed 'n' times the P( at least one head) 

=1-P ( all tail)

=1-\left ( \frac{1}{2} \right )^{n}>\frac{90}{100}

\Rightarrow \left ( \frac{1}{2} \right )^{n}<\frac{1}{10}

2^{n}>10

n\geq 4

 


Option 1)

5

Option 2)

3

Option 3)

4

Option 4)

2

Most Viewed Questions

Preparation Products

Knockout JEE Main (Six Month Subscription)

- AI Coach Study Modules, - Unlimited Mock Tests, - Study Improvement Plan.

₹ 9999/- ₹ 8499/-
Buy Now
Knockout JEE Main (Nine Month Subscription)

- AI Coach Study Modules, - Unlimited Mock Tests, - Study Improvement Plan.

₹ 13999/- ₹ 12499/-
Buy Now
Test Series JEE Main 2024

Chapter/Subject/Full Mock Tests for JEE Main, Personalized Performance Report, Weakness Sheet, Complete Answer Key,.

₹ 7999/- ₹ 4999/-
Buy Now
Knockout JEE Main (One Month Subscription)

- AI Coach Study Modules, - Unlimited Mock Tests, - Study Improvement Plan.

₹ 7999/- ₹ 4999/-
Buy Now
Knockout JEE Main (Twelve Months Subscription)

- AI Coach Study Modules, - Unlimited Mock Tests, - Study Improvement Plan.

₹ 19999/- ₹ 14499/-
Buy Now
Boost your Preparation for JEE Main 2021 with Personlized Coaching
 
Exams
Articles
Questions