Given Information:
Number of lithium batteries = n = 16
Mean life of lithium batteries = μ = 645 hours
Standard deviation of lithium batteries = σ = 31 hours
Confidence level = 95%
Required Information:
Confidence Interval = ?
Answer:
Step-by-step explanation:
The confidence interval is given by
Where μ is the mean life of lithium batteries, σ is the standard deviation, n is number of lithium batteries selected, and t is the critical value from the t-table with significance level of
tα/2 = (1 - 0.95) = 0.05/2 = 0.025
and the degree of freedom is
DoF = n - 1 = 16 - 1 = 15
The critical value (tα/2) at 15 DoF is equal to 2.131 (from the t-table)
Therefore, the 95% confidence interval is 628.5 to 661.5 hours
What does it mean?
It means that we are 95% confident that the mean life of 16 lithium batteries is within the interval of (628.5 to 661.5 hours)
Answer:
About $735.03
Step-by-step explanation:
The compound interest formula is A=P(1+r/n)^nt
P is the original amount (principal)
r is the rate
n is the number of times compounded (1 for this one since it is annual)
and t is the time compounded
Answer:
For length of side = 3 cm
Area of the square = 9 cm²
For length of side = 10.5 cm
Area of the square = 110.25 cm²
For length of side = π cm
Area of the square = 9.869 cm²
Step-by-step explanation:
The area of a square is given as :
Area = Side²
therefore,
For length of side = 3 cm
Area of the square = ( 3 cm )² = ( 3 × 3 ) cm² = 9 cm²
For length of side = 10.5 cm
Area of the square = ( 10.5 cm )² = ( 10.5 × 10.5 ) cm² = 110.25 cm²
For length of side = π cm
Area of the square = ( π cm )²
= ( π × π ) cm²
= 3.14² cm² [π = 3.14]
= 9.869 cm²
Answer:
TQ = 10
Step-by-step explanation:
The diagonal divides the square into 2 right triangles with the diagonal being the hypotenuse.
Using Pythagoras' identity in triangle TPQ
TQ² = PQ² + PT²
TQ² = 10² + 10² = 100 + 100 = 200 ( take square root of both sides )
TQ = 
= 
= 
× = 10
