Answer:
Step-by-step explanation:
This is permutation question
<u>The formula for it: </u>
- N = b!/(b-s)!, where N- number of ways, b- number of books, s- number of slots
<u>Finding the answer:</u>
- N = 7!/(7-5)! = 7!/2! = 7*6*5*4*3 = 2520
Answer:

Step-by-step explanation:
Let <em>P(A) </em>be the probability that goggle of type A is manufactured
<em>P(B) </em>be the probability that goggle of type B is manufactured
<em>P(E)</em> be the probability that a goggle is returned within 10 days of its purchase.
According to the question,
<em>P(A)</em> = 30%
<em>P(B)</em> = 70%
<em>P(E/A)</em> is the probability that a goggle is returned within 10 days of its purchase given that it was of type A.
P(E/B) is the probability that a goggle is returned within 10 days of its purchase given that it was of type B.
will be the probability that a goggle is of type A and is returned within 10 days of its purchase.
will be the probability that a goggle is of type B and is returned within 10 days of its purchase.





If a goggle is returned within 10 days of its purchase, probability that it was of type B:


So, the required probability is 
Answer:
101
Step-by-step explanation:
31+20+25+25=101
Answer:
Slove For X
x= -1
Solve for Y
Y= 10/3
Step-by-step explanation:
SO I did Elimination method
To isolate X and to solve for it
x+3y=9
3x−3y=−13
Add these equations to eliminate y:
4x=−4
Solve for X
x=-1
Now plug x back in to solve for y
234 = a + s s = students a = adults
2a = s
after you get the equations you solve. plug 2a into the above equation.
so u get
234 = a + 2a
234=3a then divide 3 from each side
78 = a
so 78 adult tickets were sold