Factorize both the numerator and denominator then equate to zero ...you'll get X
Given:
Number of passengers seated in the roller coaster = 21
Empty seats = 3
Number of cars in roller coaster = 4 (each with the same number of seats)
To find:
An equation that can be used to determine the number of seats in each car.
Solution:
Let s be the number of seats in each car.
Total number of seats in 4 cars = 4s
Using the given information,
Total number of seats = Occupied seated + Empty seats
= 21 + 3
= 24
Now, the required equation is

Therefore, the required equation is
.
Divide both sides by 4.


Therefore, the number of seats in each car is 6.
It's a line, it intersects two or more coplanar lines.
SOLUTION
This is a binomial probability. For i, we will apply the Binomial probability formula
i. Exactly 2 are defective
Using the formula, we have

Note that I made the probability of being defective as the probability of success = p
and probability of none defective as probability of failure = q
Exactly 2 are defective becomes the binomial probability

Hence the answer is 0.1157
(ii) None is defective becomes

hence the answer is 0.4823
(iii) All are defective

(iv) At least one is defective
This is 1 - probability that none is defective

Hence the answer is 0.5177