Six friends Rita, Anika, Zara, Lima, Arif, and Sayeed sit randomly in a row of six chairs. What is the probability that Rita and Anika do not sit next to each other?
A
2/3
B
1/2
C
3/4
D
3/5
উত্তরের বিবরণ
Question: Six friends Rita, Anika, Zara, Lima, Arif, and Sayeed sit randomly in a row of six chairs. What is the probability that Rita and Anika do not sit next to each other?
Solution:
Total number of possibilities = 6! = 720
Number of possibilities where Rita and Anika sit together = 5! × 2!
= 120 × 2
= 240
So the possibilities where Rita and Anika do not sit together = 720 - 240
= 480
∴Probability that Rita and Anika do not sit next to each other = 480/720
= 2/3
0
Updated: 1 month ago
How many words can be formed by using 3 letters from the word 'DELHI'?
Created: 1 month ago
A
60
B
180
C
120
D
70
Question: How many words can be formed by using 3 letters from the word 'DELHI'?
Solution:
Here we will use the Permutations for this question.
We know,
nPr, for this we have,
n = 5, Total 5 Letters
r = 3, Letters word we required
Now,
nPr = n!/(n-r)!
= 5P3
= 5!/2!
= 120/2
= 60
So, Total we can form 60 different permutation of word from Letter Delhi.
0
Updated: 1 month ago
52টি
তাসের একটি প্যাকেট থেকে
দৈবভাবে 1টি তাস টানা
হলে তাসটি টেক্কা হওয়ার সম্ভাবনা কত?
Created: 2 months ago
A
1/13
B
3/11
C
9/26
D
4/13
সমাধান:
এখানে,
মোট ঘটনার সংখ্যা = 52
মোট টেক্কার অনুকূল ঘটনা = 4
∴ তাসটি টেক্কা হওয়ার সম্ভাবনা = 4/52 = 1/13
0
Updated: 2 months ago
Two cards are drawn at random and without replacement from a standard deck of 52 cards. What is the probability that both cards are face cards?
Created: 1 month ago
A
1/26
B
1/13
C
5/52
D
11/221
Question: Two cards are drawn at random and without replacement from a standard deck of 52 cards. What is the probability that both cards are face cards?
Solution:
Total card = 52
Total face card = 3 × 4 = 12
Total ways to choose 2 cards from 52 = 52C2 = (52 × 51)/2 = 1326
Total ways to choose 2 face cards from 12 = 12C2 = (12 × 11)/2 = 66
∴ So, the probability that both cards are face cards = 66/1326
= (2 × 3 × 11)/(2 × 3 × 221)
= 11/221
0
Updated: 1 month ago
