For a Geometric sequence:
a n = a ( n-1 ) * r
In this case: a 1 = 30
a 2 = 30 * 1/2 = 15
a 3 = 15 * 1/2 = 7.5
a 4 = 7.5 * 1/2 = 3.75 = 3 3/4
Answer: The value of the fourth term is 3.75 or 3 3/4.
Answer:
50% increase
Step-by-step explanation:
half of 6 is 3 thus 50%, and vise versa.
The solution point is (4,2).
Step-by-step explanation:
Equation of straight line passing through the points (0,0) and (4,2) is given by
⇒ 2y = x ............ (1)
And the other straight line is y = - x + 6 .............. (2)
Now, solving equations (1) and (2) we get, y = - 2y + 6
⇒ 3y = 6
⇒ y = 2
And from equation (1) we get, x = 2y = 4
Therefore, the solution point is (4,2). (Answer)
Well, this problem is best solved by setting up a system of two linear equations.
A linear equation can be defined
y=mx+b
where
b=initial value (when x=0), and
m=rate of increase or decrease.
In the given example, the x-axis represents hour, and the y-axis, number of cells.
Chemical #1
initial value = b = 12000 cells
rate = m = -4000 / hr
The equation is therefore
y1=-4000x+12000......................(1)
Similarly, for chemical #2
initial value = b = 6000 cells
rate = m = -3000 / hr
The equation is therefore
y2=-3000x+6000 .......................(2)
The time the two will have an equal sized colony would represent the solution of the system of equations (1) and (2), i.e. when y1=y2
which means
-4000x+12000 = -3000x+6000
transpose and solve for x
4000x-3000x = 12000-6000
1000x=6000
x=6 hours.
At 6 hours from the start,
y=-4000x+12000 = -4000*6+12000 = -24000+12000 = -12000 cells
So the solution is x=6, y=-12000, or (6,-12000)
Physical interpretation
Since cells cannot have a negative number, the two are actually equal before six hours, when they are both zero.
Case 1: y=0 when x=3
Case 2: y=0 when x=2
Therefore, after three hours, both trials will have zero cells.
You have to judge whether to give the mathematical solution (x=6,y=-12000) or the physical interpretation (x=3, y=0) as the answer.
Answer:
here u go
Step-by-step explanation:
< DBC (angle DBC)
