1 votes 1 votes closed as a duplicate of: NIELIT 2017 DEC Scientific Assistant A - Section B: 41 If a random coin is tossed $11$ times, then what is the probability that for $7$th toss head appears exactly $4$ times? $5/32$ $15/128$ $35/128$ None of the options Probability nielit2017 probability engineering-mathematics + – Dilip Puri 7 asked Jan 3, 2018 • closed Nov 7, 2020 by Lakshman Bhaiya Dilip Puri 7 239 views comment Share Follow See 1 comment See all 1 1 comment reply Anu007 commented Jan 3, 2018 i edited by Anu007 Jan 3, 2018 reply Follow Share $\left ( \frac{35}{128} \right )$ is answer Condition is 7th toss 4 head will come. $\binom{7}{4} \times \left ( \frac{1}{2} \right )^{7}$ = $35\times \left ( \frac{1}{2} \right )^{7}$ =$\left ( \frac{35}{128} \right )$ 0 votes 0 votes Please log in or register to add a comment.