Let the dimensions be x and y
Given that the area is 40m²
xy = 40 ----------------- (1)
Given that the perimeter is 26
2(x + y) = 26
x + y = 13
x = 13 - y ---------------- Sub into (1)
(13 - y)y = 40
13y - y² = 40
y² - 13y + 40 = 0
(y - 8)(y - 5) = =
y = 8 or y = 5
The dimensions are 8 meters and 5 meters
Using the normal distribution, it is found that 0.26% of the items will either weigh less than 87 grams or more than 93 grams.
In a <em>normal distribution</em> with mean
and standard deviation
, the z-score of a measure X is given by:
- It 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, which is the percentile of X.
In this problem:
- The mean is of 90 grams, hence
.
- The standard deviation is of 1 gram, hence
.
We want to find the probability of an item <u>differing more than 3 grams from the mean</u>, hence:



The probability is P(|Z| > 3), which is 2 multiplied by the p-value of Z = -3.
- Looking at the z-table, Z = -3 has a p-value of 0.0013.
2 x 0.0013 = 0.0026
0.0026 x 100% = 0.26%
0.26% of the items will either weigh less than 87 grams or more than 93 grams.
For more on the normal distribution, you can check brainly.com/question/24663213
If you multiple 128 by 6 you will get your answer of 768.