Answer:
Gina is 12 years old
Step-by-step explanation:
First, we will have to write these statements mathematically and then solve.
Let Gina's age be x, let Gina's brother's age be y and let Gina's sister's age be z.
The second statement"Gina's older sister is twice Gina's age" can be mathematically written as: z =2 x ---------------------------(1)
The next statement "Gina's brother is half Gina's age" can be mathematically written as y = 
---------------------------------------(2)
Then the next statement "the sum of their ages is 42" can be mathematically written as: x + y + z = 42 ----------------------------(3)
We can now proceed to solve;
Substitute equation (1) and equation(2) into equation (3)
x + y + z = 42
x + + 2x = 42
Multiply through by 2
2x + x + 4x = 84
7x = 84
Divide both-side of the equation by 7
= 
x = 12
Therefore, Gina is 12 years old
Answer:
Step-by-step explanation:
1.95 g
A) (0,0) and (3,1)
1-0 divided by 3-0
Slope is 1/3
the slope represents the relationship between x and y
b) (6,2) and (-3,-1)
-1-2 divided by -3-6
Slope is 1/3
c) yes, the two triangles represent the same slope as all of the four points used are collinear (on the same line), making all the slopes equal.
Answer:
47.52% probability that among 10 randomly observed individuals fewer than 3 do not cover their mouth
Step-by-step explanation:
For each individual, there are only two possible outcomes. Either they cover their mouth when sneezing, or they do not. The probability of an individual covering their mouth when sneezing is independent of other individuals. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
In which 
is the number of different combinations of x objects from a set of n elements, given by the following formula.
And p is the probability of X happening.
According to a study done by Otago University, the probability a randomly selected individual will not cover his or her mouth when sneezing is 0.267.
This means that 
What is the probability that among 10 randomly observed individuals fewer than 3 do not cover their mouth
10 individuals, so n = 10.
In which
47.52% probability that among 10 randomly observed individuals fewer than 3 do not cover their mouth
