Answer:
17.1≤x≤23.1
Step-by-step explanation:
The formula for calculating the confidence interval is expressed as;
CI = x ± z*s/√n
x is the mean yield = 20.1
z is the 80% z-score = 1.282
s is the standard deviation = 7.66
n is the sample size = 11
Substitute
CI = 20.1 ± 1.282*7.66/√11
CI = 20.1 ± 1.282*7.66/3.3166
CI = 20.1 ± 1.282*2.3095
CI = 20.1 ±2.9609
CI = (20.1-2.9609, 20.1+2.9609)
CI = (17.139, 23.0609)
hence the required confidence interval to 1dp is 17.1≤x≤23.1
Answer:
(x, y) = (8, -3)
Step-by-step explanation:
You can substitute for x in the first equation:
3(-3y -1) +3y = 15
-6y = 18 . . . . . add 3 and simplify
y = -3 . . . . . . . divide by -6
x = -3(-3) -1 = 8 . . . . find x using the second equation
The solution to this system of equations is (x, y) = (8, -3).
Answer:
errr polynomials ahaha
so basically we can multiply the power outside of the parantheses with the exponents on the inside:
so

this will give us:
-3x^8y^4
we also unfortunately, have to use the power on the coefficient -3 as well and we cant just MULTIPLY -3 by 4, we are going to have to multiply -3 with -3 4 TIMES(anytime we see a coefficient we MUST multiply the coefficient by itself according to the number outside of the parantheses)
so:
-3*-3*-3*-3=81
final expression

One way in which to approach this problem would be to treat it as an equation of ratios and to cross multiply:
<span>[(4x + 15) / 5x)] = 1/2 could be written as:
4x + 15 1
----------- = ---
5x 2
Then 8x + 30 = 5x
3x = -30, and so x = -10 (answer). Be certain to check this answer through substitution!
</span>
5000*0.03+0.05x=275
Solve for x
X=2500
The answer is b