Answer:
(E) The bias will decrease and the variance will decrease.
Step-by-step explanation:
Given that researchers working the mean weight of a random sample of 800 carry-on bags to e the airline.
We have to find out the effect of increasing the sample size on variance and bias.
We know as per central limit theorem, sample mean follows a normal distribution with mean = sample mean
and std deviation of sample mean = std error = 
Thus std error the square root of variance is inversely proportional to the square root of sample size.
Also whenever we increase sample size the chances of bias would decrease as the sample size becomes larger
So correct answer is both bias and variation will decrease.
(E) The bias will decrease and the variance will decrease.
Answer:
3
Step-by-step explanation:
Because of the relatively large coefficients {9, 42, 49}, applying the quadratic formula would be a bit messy. Instead, I've chosen to "complete the square:"
9x^2 + 42x + 49 = 0 can be re-written as 9 [ x^2 + (42/9)x ] = -49
Dividing both sides by 9, we get [ x^2 + (42/9)x ] = - 49/9
Completing the square: [ x^2 + (42/9)x + (21/9)^2 - (21/9)^2 ] = -49/9
[ x + 21/9 ]^2 = 441/81 - 441/81 = 0
Then [ x + 21/9 ] = 0, and x = -21/9 (this is a double root).
Sorry, I'm not completely sure but I want to be helpful.
3 x 10 to the power of 8