There are 52 weeks in a year. 1 frog per week: 52 * 1 = 52
So, cloning about 1 frog per week would be reasonable.
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:
- first mechanic: $105/hour
- second mechanic: $55/hour
Step-by-step explanation:
Let r represent the rate charged by the first mechanic. Then 160-r is the rate charged by the second mechanic. The total of charges is ...
20r +5(160-r) = 2375
15r +800 = 2375 . . . . . . eliminate parentheses
15r = 1575 . . . . . . . . . . . . subtract 800
r = 105 . . . . . . . . . . . . . . . divide by 15. First mechanic's rate.
160-r = 55 . . . . . Second mechanic's rate
The first mechanic charged $105 per hour; the second, $55 per hour.
The ration of a triangle is the same as a is to b as b is to c and c is to a.
4 +5 = 9 and 12 + 3 =15 and there is more than this
hope I helped
