30(30 – x) = 540
distribute
900 -30x = 540
subtract 900 from each side
-30x = -360
divide by -30
x =12
Answer:
a = 90
b = 28
c = 68
d = 22
Step-by-step explanation:
Answer:
- half-life: 95.3 days
- 60% life: 70.2 days
Step-by-step explanation:
a) The proportion remaining (p) after d days can be described by ...
p = (1 -0.73)^(d/180) = 0.27^(d/180)
Then p=1/2 when ...
0.50 = 0.27^(d/180)
log(0.50) = (d/180)log(0.27)
180(log(0.50)/log(0.27) = d ≈ 95.3
The half-life is about 95.3 days.
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b) For the proportion remaining to be 60/100, we can use the same solution process. In the end, 0.50 will be replaced by 0.60, and we have ...
d = 180(log(0.60)/log(0.27) ≈ 70.2 . . . days
60 mg will remain of a 100 mg sample after 70.2 days.
Answer:
27 m
Step-by-step explanation:
The position of a body is given by :
We need to find the total distance traveled by the body from t=0 to t=3.
At t = 0,
At t = 3 s,
So, the total distance from t=0 to t=3 is equal to 27 m.
