Answer:
And using the probability mass function we got:
Step-by-step explanation:
Let X the random variable of interest, on this case we now that:
The probability mass function for the Binomial distribution is given as:
Where (nCx) means combinatory and it's given by this formula:
And we want to find the following probability:
And using the probability mass function we got:
Answer: 1:15pm
Step-by-step explanation:
Let the initial number of girls be x, this represents 40% of the dancers.
Total number of dancers will therefore be:
100/40*x=2.5x
When 15 more girls joined, the new number of girls was:
x+15 this represents the total percentage of 52%. The new number of dancers became:
2.5x+15:
therefore the new percentage of girls can be expressed as follows:
(new number of girls)/(new number of dancers)×100
(x+15)/(2.5x+15)×100=52
(x+15)/(2.5x+15)=0.52
x+15=0.52(2.5x+15)
x+15=1.3x+7.8
15-7.8=1.3x-x
7.2=0.3x
x=7.2/0.3=24
The number of students after additional number of girls will be:
2.5x+15
=2.5×24+15
=60+15
=75 students
