60% of 35 can be found by multiplying .6 x 35 = 21. At least 21 members must be present to vote
The correct answer is the first one.
Two events are said to be Disjoint or Mutually Exclusive if the two events can not happen at the same time.For example when we throw a die getting an even number is disjoint to getting an odd number.
I.e Probability(A∩B)=0
Let me explain this concept through venn diagram.
Pr[A∪B]=0.7, Pr[A]=0.25
Since events are Disjoint
Pr[A∩B]=0
Pr[A∪B]=Pr[A] + Pr[B]
0.7=0.25 +Pr[B]
0.7-0.25=Pr[B]
⇒Pr[B]=0.45=45/100=9/20
Now events are said to be independent if Pr[A and B]=Pr[A] ×Pr[B]
Events are said to be independent if occurrence of one is not affected by occurrence of other.For example getting multiple of 2 as one event and getting multiple of 3 as second event when we throw a die.
Pr[A∪B]=0.7, Pr[A]=0.25
Pr[A∪B]= Pr[A]+ Pr[B]-Pr[A∩B]
But Pr[A∩B]= Pr[A] ×Pr[B]
⇒Pr[A∪B]= Pr[A]+ Pr[B]- Pr[A] ×Pr[B]
⇒0.7=0.25+p-0.25×p
⇒0.7-0.25=p- 0.25 p
⇒0.45=0.75 p
⇒p= 0.45/0.75
⇒p =3/5
Sorry i cant see the picture
X,y - two numbers (x > y)
(1) x + y = 67 ⇒ x = 67 - y
(2) x - 4 = 2y
subtitute (1) to (2)
67 - y - 4 = 2y
63 - y = 2y |add y to both sides
63 = 3y |divide both sides by 3
y = 21
subtitute the value of y to (1)
x = 67 - 21 = 46
Answer: 21 and 46.