Answer:
The even numbers between 0 and X represents an arithmetic sequence with a common difference of 2
The rule of arithmetic sequence = a + d(n - 1)
Where a is the first term and n is the number of terms
So, for the even numbers between 0 and X
The first term = a = 0
d = 2
So, we need to find n at the last term which is X
∴ X = 0 + 2 ( n -1 )
∴ n - 1 = X/2
∴ n = X/2 + 1
The sum of the arithmetic sequence = (n/2) × (2a + (n−1)d)
Substitute with a and d and X
So, the sum = (n/2) * (2*0 + (n−1)*2)
= (n/2) * ((n−1)*2)
= n(n-1)
= (X/2 + 1) * (X/2)
= X/2 by (X/2 + 1)
So, The quick way to add all even numbers between 0 and X always works.
It is given the probability that a dancer like ballet is 0.35
So, P(B) = 0.35
It is given the probability that a dancer like tap is 0.45
So, P(T)= 0.45
The probability that he likes both ballet and tap is 0.30
So, 
the probability that the dancer likes ballet if we know she likes tap. This is the case of conditional probability.
So, 

= 0.666
= 0.67
Therefore, the probability that the dancer likes ballet if we know she likes tap is 0.67.
Option 3 is the correct answer.
Answer:
I thought is should only take pic of 1 question
Step-by-step explanation:
Rick Astley,Donald trump,Obama,China has conora
Answer:
z = 69
Step-by-step explanation:
43 - 20 = z/ 3
23 = 
cross multiply
z = 23 x 3
z =69