Answer:

Step-by-step explanation:
From the question, we have the following condition:

We know that each student who hears the rumor tells it to a student picked at random from the dormitory (excluding, of course, himself/herself and the person from whom he/she heard the rumor)
The 3rd student can therefore tell the rumour to n-2 students but only n-3 will accept it.

Consequently, the 4th student must not tell the 1st and second students.

We can rewrite this to observe a pattern:



Hence, the probability that the rumor is told r times without coming back to a student who has already is:

See attachment for complete question
Do you need help with all of them?
Answer:
x=8
Step-by-step explanation:
normally it would be 2x-1=
x+9 so now we have to combine the x into one fraction which will be 2x-1=
+9 now for my way i will be taking the -1 to the other side and when that happens its going to become positive so now the answer will be 2x=
+10 ok so now we have to have the x's to the same side so i have to drag the fraction to the other side and making it positive which will conclude into 1.25x=10 and now 10 divided by 1.25 is 8 so the answer is x=8 (sorry for the ok nows) hope this helped
Answer:
20:25:15
Step-by-step explanation:
60 sweets alltogether