Answer:
The younger brother is 16 years old.
Step-by-step explanation:
The younger brother is aged x.
It follows that the older brother is aged x+3.
x + (x+3) = 35
2x + 3 = 35
2x = 32
x = 16
Answer:
-3.3
Step-by-step explanation:
I had to take a second look because the image and the description wasn't the same, but after simplifying the value, i got -3.3
Answer:
99.38%
Step-by-step explanation:
We have that the mean (m) is equal to 124, the standard deviation (sd) 6.4 and the sample size (n) = 64
They ask us for P (x <126)
For this, the first thing is to calculate z, which is given by the following equation:
z = (x - m) / (sd / (n ^ 1/2))
We have all these values, replacing we have:
z = (126 - 124) / (6.4 / (64 ^ 1/2))
z = 2.5
With the normal distribution table (attached), we have that at that value, the probability is:
P (z <2.5) = 0.9938
The probability is 99.38%
Answer:
&
Step-by-step explanation:
Column 1:
500 x 5% = 250
$250 in interest each year
Column 2:
500 + 250 = 750
<em>$750 at the end.</em>
Answer:
The coefficient 1.5 means her winning distance is 1.5 times the mean (add them up and divide the total number by the number of numbers) of her three best practices.
Some other helpful stuff:
Let's say Rosa's three practice distances were 1.6 meters, 1.7 meters, and 2.1 meters. To get the mean of these, add them up(5.4) and divide by the number of numbers, three(1.8). Let's say her winning distance was 2.7. If you divide the winning time by the mean of her three best practices, you get 1.5. This means that 2.7 = 1.5(1.8), or, 2.7 = 1.5M.
