Answer:
100
Step-by-step explanation:
Ratio is a fraction, so ratio of boys to girls would be written as [let boys be "b" and girls be "g"]:

Also, there are 250 more girls than boys, so we can write:
g = 250 + b
Lets substitute this into "g" of the ratio we wrote and cross mulitply and solve for b:

The number of boys = 100
Answer: %0.00100010001
Step-by-step explanation:
Answer:
54
Step-by-step explanation:
9*6=54
6 rows of 9 titles
Answer:
Required Probability = 0.605
Step-by-step explanation:
Let Probability of people actually having predisposition, P(PD) = 0.03
Probability of people not having predisposition, P(PD') = 1 - 0.03 = 0.97
Let PR = event that result are positive
Probability that the test is positive when a person actually has the predisposition, P(PR/PD) = 0.99
Probability that the test is positive when a person actually does not have the predisposition, P(PR/PD') = 1 - 0.98 = 0.02
So, probability that a randomly selected person who tests positive for the predisposition by the test actually has the predisposition = P(PD/PR)
Using Bayes' Theorem to calculate above probability;
P(PD/PR) =
=
=
= 0.605 .