If x² = 196, then we must do the inverse (square root) to find x. However, the square root of any positive number will always be ± (plus or minus).
That means you have to do:
√196 = x
x = <span>±14.
We can check this by doing:
14 </span>× 14 = 196
-14 × -14 = 196
Therefore the answer is B) -14, 14.
The answer in the simplest form : 3/4
Answer: 1.303639
Step-by-step explanation:
The t-score for a level of confidence 
is given by :_
, where df is the degree of freedom and 
is the significance level.
Given : Level of significance : 
Then , significance level : 
Sample size : 
Then , the degree of freedom for t-distribution: 
Using the normal t-distribution table, we have
Thus, the t-score should be used to find the 80% confidence interval for the population mean =1.303639
Answer:
Mean age: 48
Standard deviation: 4
Step-by-step explanation:
a) Mean
The formula for Mean = Sum of terms/ Number of terms
Number of terms
= 42 + 54 + 50 + 54 + 50 + 42 + 46 + 46 + 48+ 48/ 10
= 480/10
= 48
The mean age is 48
b) Standard deviation
The formula for Standard deviation =
√(x - Mean)²/n
Where n = number of terms
Standard deviation =
√[(42 - 48)² + (54 - 48)² + (50 - 48)² +(54 - 48)² + (50 - 48)² +(42 - 48)² + (46 - 48)² + (46 - 48)² + (48 - 48)² + (48 - 48)² / 10]
= √-6² + 6² + 2² + 6² + 2² + -6² + -2² + -2² + 0² + 0²/10
=√36 + 36 + 4 + 36 + 4 + 36 + 4 + 4 + 0 + 0/ 10
=√160/10
= √16
= 4
The standard deviation of the ages is 4
Fun
n=number of nickles
q=number of quarters
d=number of dimes
4 more dmes than nickles, 3 more quarters than dimes
d+4=n
q=3+d
total value is 455 cents
10d+5n+25q=455
divide both sides by 5 to simplify
2d+n+5q=91
now we convert all to one coin
q=3+d and n+4=d
subsitute 3+d for q and n+4 for d
2(n+4)+n+5(3+d)=91
2(n+4)+n+5(3+n+4)=91
2(n+4)+n+5(n+7)=91
2n+8+n+5n+35=91
8n+43=91
minus 43 both sides
8n=48
divide both sides by 8
n=6
sub back
n+4=d
6+4=d
10=d
q=3+d
q=3+10
q=13
6 nickles
10 dimes
13 quarters
