<u>Solution-
</u>
A researcher placed a petri dish with 32,000 bacterial cells. One hour after being placed in the vacuum chamber, the number of cells in the petri dish had halved. Another hour later, the number of cells had again halved.
This can be represented as exponential decreasing function,

Where,
-
a = starting amount = 32000
- r = rate = 50% = 0.5 as the sample becomes halved in each hour
- x = hours
Putting the values,


y-intercept means, where x=0, so

The coordinate of this poin will be (0, 32000)
This means when x=0 or at the starting of the research, the number of bacteria cells was 32000.
After 3 hours, number of bacteria cells will be,



The coordinate of this point will be (3, 4000)
Answer:
98% confidence interval is (-0.105 , 0.265)
Step-by-step explanation:
n1 = 75 n2 = 75
X1 = 48 X2 = 42
P1 = X1/N1 = 0.64 P2 = X2/N2 = 0.56
98% confidence interval for difference between two proportions is :
P1 - P2 <u>+</u> Z 
= 0.08 <u>+</u> 0.185
= (-0.105 , 0.265)
98% confidence interval is (-0.105 , 0.265)
Answer:
Ruth's 1931 salary was equivalent to a 2015 salary of $1,247,368.
Step-by-step explanation:
This question can be solved by a rule of three.
Government statistics show a consumer price index of 15.2 for 1931 and 237 for 2015.
This means that $15.2 in 1931 is equivalent to $237 in 2015. So
$15.2 in 1931 - $237 in 2015
$80,000 in 1931 - $x in 2015



Ruth's 1931 salary was equivalent to a 2015 salary of $1,247,368.
We have two equations that were solved by Nikki and Jonathon:
Equating the above two:
⇒ 1.3x + 1.6 = -2.7x + 3.2
⇒ 4x = 1.6
⇒ x = 0.4
Hence, substituting the value of x in one of the equations we get:
y = 1.3×0.4 + 1.6 = 2.12
So the solution is (0.4, 2.12)
Jonathon's solution was (0.4, 2.12) and Nikki's was (2.25, 0.5). Hence Jonathon gave the correct solution.