To solve this problem, we must set up a system of equations. In this case, let's let Maggie's age be represented by the variable m and her brother's age be represented by the variable b. We are told that the sum of their ages is 24, which gives us our first equation: m + b = 24. We can construct our next equation from the first sentence of given information: b = 2m - 3. This makes our system of equations:
m + b = 24
b = 2m - 3
To solve, we are going to substitute the value for b in terms of m given by the second equation into the first equation for the variable b.
m + b = 24
m + 2m - 3 = 24
To simplify, we must first combine the variable terms on the left side of the equation using addition.
3m - 3 = 24
Next, we should add 3 to both sides of the equation to get the variable term alone on the left side of the equation.
3m = 27
Finally, we should divide both sides by 3 in order to get the variable m alone.
m = 9
Therefore, Maggie is 9 years old (using the first equation and substituting in this value you can find that her brother is 15 years old).
Hope this helps!
Answer:
1. z = -1.91429
The z score tells us that the head circumference of the girl with the down syndrome ( 44.5 cm) is 1.91429 standard deviations below the mean or average head circumference
2. 2.7792%
Step-by-step explanation:
1. Relative to the WHO data, what is this girls z-score?
z score formula is:
z = (x-μ)/σ, where
x is the raw score = 44.5 cm
μ is the population mean = 47.18cm
σ is the population standard deviation = 1.40cm
z = 44.5 - 47.18/1.40
z = -1.91429
What does the z score tell us?
The z score tells us that the head circumference of the girl with the down syndrome ( 44.5 cm) is 1.91429 standard deviations below the mean or average head circumference
2. Using the WHO data in a normal model, what percentage of the girls has a head circumference that is smaller than the girl with Down's Syndrome?
z score = -1.91429
Probability value from Z-Table:
P(z =-1.91429) = P(x<44.5) = 0.027792
Converting to percentage = 0.027792 × 100
= 2.7792%
Answer:
$2,860
Step-by-step explanation:
2,500 * 3.8% = 90 in interest a year
so
90 * 4 = 360 in interest
add that to what she put in
2,860
Answer: 110 Women !
Step-by-step explanation:
Call their numbers 4x to 5x.
Since there are a total of 198 people,
4x + 5x = 198
9x = 198
x = 22
so that there are
88 men and 110 women.