Answer:
<em>The greatest number of song he can practice in a week is 2.</em>
Step-by-step explanation:
Suppose, the greatest number of song he can practice in a week is 
He practices each song for
hours. So, the total time required for practicing
number of songs
hours.
Given that, he practices his guitar for 9 hours each week.
So, the equation will be......

<em>(Rounded as the greatest whole number)</em>
Thus, the greatest number of song he can practice in a week is 2.
We assume the lunch prices we observe are drawn from a normal distribution with true mean
and standard deviation 0.68 in dollars.
We average
samples to get
.
The standard deviation of the average (an experiment where we collect 45 samples and average them) is the square root of n times smaller than than the standard deviation of the individual samples. We'll write

Our goal is to come up with a confidence interval (a,b) that we can be 90% sure contains
.
Our interval takes the form of
as
is our best guess at the middle of the interval. We have to find the z that gives us 90% of the area of the bell in the "middle".
Since we're given the standard deviation of the true distribution we don't need a t distribution or anything like that. n=45 is big enough (more than 30 or so) that we can substitute the normal distribution for the t distribution anyway.
Usually the questioner is nice enough to ask for a 95% confidence interval, which by the 68-95-99.7 rule is plus or minus two sigma. Here it's a bit less; we have to look it up.
With the right table or computer we find z that corresponds to a probability p=.90 the integral of the unit normal from -z to z. Unfortunately these tables come in various flavors and we have to convert the probability to suit. Sometimes that's a one sided probability from zero to z. That would be an area aka probability of 0.45 from 0 to z (the "body") or a probability of 0.05 from z to infinity (the "tail"). Often the table is the integral of the bell from -infinity to positive z, so we'd have to find p=0.95 in that table. We know that the answer would be z=2 if our original p had been 95% so we expect a number a bit less than 2, a smaller number of standard deviations to include a bit less of the probability.
We find z=1.65 in the typical table has p=.95 from -infinity to z. So our 90% confidence interval is

in other words a margin of error of
dollars
That's around plus or minus 17 cents.
For the first step you need to convert between feet in real life and feet in the cartoon drawing. 1/2 inch in cartoon is 3 feet in real life, so 1 foot in real life was 1/6 inch in cartoon. Her hair was 21 feet in real life, therefore it was 21/6, or 7/2 inches long in the cartoon. For the second step you need to explain what I just said, In your own words! Please do not simply copy down my solution.
Answer:
+5
Step-by-step explanation:
So you can see the 5 pattern, so you add 9+5= 14 which goes in the middle square and 14+5=18 in the left square
Now between 18 and 11 it is 7 so you subtract 7 which equals 4 then - 5= -1 then -5= -6
Answer:
square root of 36, 6.1, 6 and 1/2
Step-by-step explanation:
square root of 36=6
6 1/2=6.5
6, 6.1, 6.5