An article in the Journal of Composite Materials describes the effect of delamination on thenatural frequency of beams made from composite laminates. Five such delaminated beams were subjected to loads, and the resulting frequencies were as follows (in Hz): 230.66, 233.05, 232.58, 229.48, 232.58
(a) Find a 90% two-sided CI on mean natural frequency. Round your answers to 2 decimal places.
(b) Do the results of your calculations support the claim that mean natural frequency is 235 Hz?
(A). <= U<=
(B). YES OR NO ?

(230.21 ; 233.13)

Step-by-step explanation:

Given the data :

230.66, 233.05, 232.58, 229.48, 232.58

To calculate the 90% CI

WE obtain the mean and standard deviation of the sample data :

Mean of sample, ΣX /n = 1158.35/5 = 231.67

The standard deviation of the sample, s = 1.531 (Using calculator).

(The 90% Tcritical value, 2 sided, df = 4) = 2.132

The confidence interval, CI :

Mean ± Tcritical * s/√n

C.I = 231.67 ± (2.132 * (1.531/√5)

C. I = 231.67 ± 1.4597

(231.67 - 1.4597) ; (231.67 + 1.4597)

(230.21 ; 233.13)

i do not know the answer i am sorry

stew reads at the fastest rate of 265 words per minute.

step-by-step explanation:

it's a given that felicia reads at 260 word per minute and on connie's graph we can see that she reads 200 words per minute. since stew's table tells us that he read 795 in 3 minutes, we can divide 795 by 3 to find out how many words he reads per minute.

795/3 = 265

stew reads 265 words per minute - he reads at the fastest rate since felecia reads at 260 words per minute and connie reads at 200 words per minute.

stew (265) > felecia (260) > connie (200)