Answer:
95% confidence interval = ( 28.9485, 40.1515 )
Step-by-step explanation:
sample size( n ) = 52
mean value ( x )= 34.55
std ( б ) = 20.12
H0 : <em>u </em>≤ 30
Ha : u > 30 ( claim )
95% confidence interval for mean SPF level ( df = 51 )
= mean value ±
95% confidence interval = ( 28.9485, 40.1515 )
we cannot reject H0
Answer:
y=1x or just y=x might be a good line of best fit for this data
Answer:
x ≈ - 6.74, 0.74
Step-by-step explanation:
x² + 6x - 5 = 0 ( add 5 to both sides )
x² + 6x = 5
To complete the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(3)x + 9 = 5 + 9
(x + 3)² = 14 ( take square root of both sides )
x + 3 = ± ( subtract 3 from both sides )
x = - 3 ±
Then
x = - 3 - ≈ - 6.74 ( to the nearest hundredth )
x = - 3 + ≈ 0.74 ( to the nearest hundredth )
