Circumference = 2*pi*radius = 2*3.14*3 = 18.84 ft
Area = pi*radius^2 = 3.14*3*3= 28.26 ft^2
There are 187 nickels and 66 dimes in the jar.
Step-by-step explanation:
Given,
Total coins = 253
Value of coins = $15.95 = 15.95*100 = 1595 cents
Value of each nickel = 5 cents
Value of each dime = 10 cents
According to given statement;
x+y=253 Eqn 1
5x+10y=1595 Eqn 2
Multiplying Eqn 1 by 5

Subtracting Eqn 3 from Eqn 2

Dividing both sides by 5

Putting y=66 in Eqn 1

There are 187 nickels and 66 dimes in the jar.
Keywords: linear equation, elimination method
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Answer: The number of first-year residents she must survey to be 95% confident= 263
Step-by-step explanation:
When population standard deviation (
) is known and margin of error(E) is given, then the minimum sample size (n) is given by :-
, z* = Two-tailed critical value for the given confidence interval.
For 95% confidence level , z* = 1.96
As,
= 8.265, E = 1
So, ![n= (\dfrac{1.96\times8.265}{1})^2 =(16.1994)^2\\\\= 262.42056036\approx263\ \ \ [\text{Rounded to the next integer}]](https://tex.z-dn.net/?f=n%3D%20%28%5Cdfrac%7B1.96%5Ctimes8.265%7D%7B1%7D%29%5E2%20%3D%2816.1994%29%5E2%5C%5C%5C%5C%3D%20262.42056036%5Capprox263%5C%20%5C%20%5C%20%5B%5Ctext%7BRounded%20to%20the%20next%20integer%7D%5D)
Hence, the number of first-year residents she must survey to be 95% confident= 263
I think maybe 3) would make the most sense because she wants a random sample of students and the other options are specific on the type of students.