$24 x 6 = 144 Minus the $6 she spent per week -$36 = $108
I guess that is what you meant when you typed "she saved $24 each week she saves $6???
Answer:
Yes, both np and n(1-p) are ≥ 10
Mean = 0.12 ; Standard deviation = 0.02004
Yes. There is a less than 5% chance of this happening by random variation. 0.034839
Step-by-step explanation:
Given that :
p = 12% = 0.12 ;
Sample size, n = 263
np = 263 * 0.12 = 31.56
n(1 - p) = 263(1 - 0.12) = 263 * 0.88 = 231.44
According to the central limit theorem, distribution of sample proportion approximately follow normal distribution with mean of p = 0.12 and standard deviation sqrt(p*(1 - p)/n) = sqrt (0.12 *0.88)/n = sqrt(0.0004015) = 0.02004
Z = (x - mean) / standard deviation
x = 22 / 263 = 0.08365
Z = (0.08365 - 0.12) / 0.02004
Z = −1.813872
Z = - 1.814
P(Z < −1.814) = 0.034839 (Z probability calculator)
Yes, it is unusual
0.034 < 0.05 (Hence, There is a less than 5% chance of this happening by random variation.
I’m not sure about this question
Answer:
51. A/P = (2.2t +25)/(2.6t +29)
52. A/P for t=0 is about 0.862
A/P for t=4 is about 0.858
Step-by-step explanation:
51. The ratio of the two given functions is ...
r(t) = A/P
r(t) = (2.2t +25)/(2.6t +29)
__
52. Fill in the required numbers and do the arithmetic.
r(0) = (0 +25)/(0 +29) = 25/29
r(0) ≈ 0.862
_
r(4) = (2.2·4 +25)/(2.6·4 +29) = 33.8/39.4
r(4) ≈ 0.858
The salary ratio is approximately flat at 0.86 over the 4-year period. It is declining slightly each year.
