i wasn't sure on how to explain it so i just attached ur answer
A) 2007
b) 120
c) the donations are decreasing as years increase
(4.81 x 10^3) + (7.913 x 10^5)
(4810)+(791300) = 796,110 OR (79611 x 10)
Answer:
Step 1: Multiply the entire first equation by 2.
Step 2: Rewrite the system of equations, replacing the first equation with the new equation.
Step 3: Add the equations.
Step 4: Solve for x.
Step 5: Find the y-value by substituting in 3 for x in either equation.
Step 6: Identify the solution as an ordered pair.
Answer:
A)σ_M = 1.2634
B) CI = (36.564, 41.516)
C) σ_M = 0.1151
Step-by-step explanation:
A) Formula for standard error is;
σ_M = σ/√n
We are given;
Mean; x¯ = 39.04
Standard deviation; σ = 11.51
Sample size; n = 83
Thus;
Standard error; σ_M = 11.51/√83
σ_M = 1.2634
B) formula for confidence interval is;
CI = x¯ ± z(σ_M)
z is critical value
At 95% Confidence interval, z = 1.96
Thus;
CI = 39.04 ± 1.96(1.2634)
CI = (39.04 + 2.476) and (39.04 - 2.476)
CI = (36.564, 41.516)
C) sample size is now increased to 10000
Thus,standard error is calculated as;
σ_M = 11.51/√10000
σ_M = 0.1151