Answer:
a) 20.16; b) 20.49 and 21.51
Step-by-step explanation:
We use z scores for each of these. The formula for a z score is
.
For part a, we want the 20th percentile; this means we want 20% of the data to be lower than this. We find the value in the cells of the z table that are the closest to 0.20 as we can get; this is 0.2005, which corresponds with a z score of -0.84.
Using this, 21 as the mean and 1 as the standard deviation,
-0.84 = (X-21)/1
-0.84 = X-21
Add 21 to each side:
-0.84+21 = X-21+21
20.16 = X
For part b, we want the middle 39%. This means we want 39/2 = 19.5% above the mean and 19.5% below the mean; this means we want
50-19.5 = 30.5% = 0.305 and
50+19.5 = 69.5% = 0.695.
Looking these values up in the cells of the z table, we find those exact values; 0.305 corresponds with z = -0.51 and 0.695 corresponds with z = 0.51:
-0.51 = (X-21)/1
-0.51 = X-21
Add 21 to each side:
-0.51+21 = X-21+21
20.49 = X
0.51 = (X-21)/1
0.51 = X-21
Add 21 to each side:
0.51+21 = X-21+21
21.51 = X
Answer:
The weight that separate the top 8% by 5.2605 and the weight that separate bottom 8% by 5.1195.
Step-by-step explanation:
We are given that
Mean,
Standard deviation,
We have to find the two weights that separate the top 8% and the bottom 8%.
Let x1 and x2 the two weights that separate the top 8% and the bottom 8%.
Z-value for p-value =0.08 =
For 8% bottom
For 8% top
p-Value=1-0.08=0.92
Z- value=1.41
Now,
(x1,x2)=(5.1195,5.2605)
Answer:
From least to greatest
23* 1/4, 23* 2/2, 23* 13/5
Explanation
In order to do this without multiplication, place the fractions in ascending order.
The denominators of these fractions have 20 as a common multiple.
2/2 • 10 = 20/20
1/4 • 5 = 5/20
13/5 • 4 = 52/20
From this it logically follows that the fractions in ascending order are:
1/4, 2/2, 13/5
Therefore the products in ascending order are:
23* 1/4, 23* 2/2, 23* 13/5
Lindsay ordered 86 blankets and 43 quilts. This totals 129 items.