Answer:
Weights of at least 340.1 are in the highest 20%.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:

a. Highest 20 percent
At least X
100-20 = 80
So X is the 80th percentile, which is X when Z has a pvalue of 0.8. So X when Z = 0.842.




Weights of at least 340.1 are in the highest 20%.
N + d = 21
0.5n + 0.10d = 1.35
5n + 10d = 135
d = 21-n
5n + 210 - 10n = 135
-5n = -75
n = 15
d = 6
Give the other person brainliest just answering so they can get it
Since each term contains x, x= 0 is one answer Also as x^2 is a factor it has duplicity 2.
Factoring:-
x^2 (x^2 - 4x + 3) = 0
x^2( x - 3)(x - 1) = 0
so x = 3 and x = 1 are also zeros
Answer:- x = 0 (duplicity 2), x = 1 and x = 3.
12.3 or 12 3/10
4.5 + 7.8 = 12.3
or
4 10/20 + 7 16/20 = 11 26/20
11 26/20 can be simplified to 12 6/20 and further simplified to 12 3/10