Answer: 4 years
Step-by-step explanation:
A(0) has to be amount at start. Assume that's 5mg
Then A(t) = 5×(0.5)^(0.25t) = 5×2^(-t/4),
(also known as 5 exp(-λ t) with λ = ln(2)/4, incidentally).
We need to such that A(t) = 2.5mg, or 2^(-t/4) is 1/2, which happens when -t/4 is -1, or t is 4.
Answer:that’s hard
Step-by-step explanation:nope
Nope
-2x^2=-15-5
-2x^2=-10
x^2=-5
X≠R i am not quite sure but...hope it helps :)
Answer:
(c) 3,5 is the correct answer
Answer:(a) margin error = 2.4%
(b) The margin error gives the measure in percentage of how the population parameter determined differ from the real population statistics or value.
(c) in 90% of the samples of teens in the country, the percent who go online several times a day will be within 50.6% and 55.4%. of the estimated 100%
Step-by-step explanation:
Using the proportion formulae
Margin error = z √p(1-p)/n
n= 1170, p = 53% = 0.53, 1-p = 0.47
and the z value at 90% C.I = 1.645
M error= 1.645 √0.53×0.47/1170
Margin error = 0.024 = 0.024 ×100
Margin error = 2.4%
53 - 2.4 = 50.6% and 53 + 2.4 = 55.4%
In other words 90% of the time: the number of teens who go online several time a day will be between 50.6 and 55.4%.