Answer:
b. Invalid, because the sample may not be representative of the population.
Step-by-step explanation:
A sample of around 10% of the population is needed to be representative.
In this question:
We have a population of 500,000, and a sample of 10,000.
10,000/500,000 = 1/50 = 0.02 = 2% of the population, so not representative, and option b is correct.
a- is -28 and i’m working out the rest for you now
I think its 2.8.
Reason why:
4/5 = 0.8
Then the 2 would a whole number...
so 2.8.
Answer:
(5, - 4 )
Step-by-step explanation:
Given the 2 equations
2x + 3y = - 2 → (1)
3x - y = 19 → (2)
Multiplying (2) by 3 and adding to (1) will eliminate the y- term
9x - 3y = 57 → (3)
Add (1) and (3) term by term to eliminate y
(2x + 9x) + (3y - 3y) = (- 2 + 57), that is
11x = 55 ( divide both sides by 5 )
x = 5
Substitute x = 5 into either of the 2 equations and solve for y
Substituting into (1)
2(5) + 3y = - 2
10 + 3y = - 2 ( subtract 10 from both sides )
3y = - 12 ( divide both sides by 3 )
y = - 4
Solution is (5, - 4 )
Answer:
See Explanation
Step-by-step explanation:
Now;
From;
P=Poe^kt
Where;
P = population at time=t
Po = population initially present
k = growth rate
t = time taken
a) The function is;
P= 112,000e^0.04t
b) In the year 2004, the population will be
P= 112,000e^0.04(6)
P= 142380
c) 200,000 =112,000 e^0.04t
200,000/112,000 = e^0.04t
1.786 = e^0.04t
ln 1.786 = ln e^0.04t
ln 1.786= 0.04t
t = ln 1.786/0.04
t = 14.5 years
