Answer:
Distribution 4, mean is 20 and standard deviation is 3.2
Step-by-step explanation:
The standard deviation tells us on average how far each of our data values is from the mean. A standard deviation that is larger than the others will mean a distribution that is more spread out than the others; 3.2 is the largest standard deviation, so Distribution 4 has the greatest spread.
Answer:
the height is 20
Step-by-step explanation:
you should set a equation first:
12/15=x/25
and then cross multiply
to get x=20
Let's set up some simultaneous equations. Let the number of nickels be n, and the number of quarters be q. Now I'm from England so I had to look up the value of a nickel (I could guess the quarter though to be 25c), but apparently it's 5c
Okay we know that the total value of the coins is 150. This gives:
25q + 5n = 150
Rearranging to make n the subject:
n = 30 - 5q
Next, we use the second statement:
n = 2q - 5
Substituting this into the first equation:
2q - 5 = 30 - 5q
7q = 35
q = 5
Putting this value for q into the first equation:
n = 30 - 5(5) = 5
Hence he has 5 of each coin. I hope this helps :)
I think the answer is -9.