Answer:
39
Step-by-step explanation:
From the calculation, the growth rate is 0.88.
<h3>What is the growth rate?</h3>
To find the relative growth rate
P1 = Poe^rt
P2 = Poe^rt
Thus;
1920 = Poe^4r ------ (1)
1966080 =Poe^12r -------(2)
P2/P1 gives;
1966080/1920 = Poe^12r/Poe^4r
1024 = e^12r/e^4r
1024 =e^8r
1024 = (e^r)^8
2^10 = (e^r)^8
e^r = 2^1.25
e^r = 2.38
r = ln(2.38)
r = 0.88
The initial size of the culture is;
1920 = Poe^(0.88 * 4)
Po = 1920/e^(0.88 * 4)
Po = 57
The expression for the exact number of bacteria after t hours is
P(t) = 57e^0.08t
The growth (in bacteria per hour) after 9.5 hours is
P(t) = 57e^(0.88 * 9.5)
P(t) = 243544
For the number to reach 72,000;
72,000 = 57e^0.88t
72,000/57 = e^0.88t
ln 126 = ln[e^0.88t]
4.8 = 0.88t
t = 4.8/0.88
t = 5.5 hours
Learn more about exponential growth;brainly.com/question/13674608
#SPJ1
Answer:
Equation of midsegment line: y = (-1/4)x + 2.
Step-by-step explanation:
If the parallel sides of a trapezoid are contained by the lines:-
y = (-1/4)x +5 and y = (-1/4)x - 1
Midsegment of any trapezoid is the line segment
1. that is parallel to pair of parallel side of trapezoid and
2. that passes through the middle of the trapezoid and cuts the other two sides into equal-half.
It means the midsegment would have same slope as the parallel lines and y-intercept would be in the middle of intercepts of parallel lines.
So y = mx + b
where m = -1/4 and b = (5 - 1)/2 = 4/2 = 2.
Hence, the equation of midsegment would be y = (-1/4)x + 2.
X = unknown number
10x - 16 = 2x
Subtract 10x from both sides to isolate the variable on the right side of the equation.
-16 = -8x
Divide both sides by -8 to get x alone.
2 = x