Answer:
(a) The 26th percentile for the number of chocolate chips in a bag is 1185
(b) The number of chocolate chips in a bag that makes up the middle 96% of the bags is between 1020 and 1504
Step-by-step explanation:
From the question, we have the following values:
μ =1262 and σ =118
(a) Let the value of x represents the 26th percentile. So the 26th percentile means 26% data is less than x. We can use the standard normal table to get the particular z-value that corresponds to this percentile.
P( Z<-0.65 )=0.2578 which is approximately 0.26
So for 26th percentile z-score will be -0.65.
Mathematically;
z-score = (x-mean)/SD
-0.65 = (x-1262)/118
-76.7 = x -1262
x = 1262-76.7 = 1185.3
This value is approximately 1,185
(b) Using a graph of standard normal distribution curve, if middle is 96% , then at both tails 2% each.
From z-table, we can find the closest probability;
P(-2.05<z<2.05) = 0.96
So we have two x values to get from the individual z-scores
-2.05 = (x-1262)/118
x = 1020(approximately)
For 2.05, we have
2.05 = (x-1262)/118
x = 1262 + 2.05(118) = 1504 (approximately)
The roots are located at (2,0) and (4,0)
In short, the roots are x = 2 and x = 4
The term "x intercept" is another way of saying "root". Both describe the location where the graph crosses the x axis.
Answer:
Probably 128 km/h, but maybe 98.5 km/h. See below.
Step-by-step explanation:
What does "at the same time" mean?
If it means that he covered the 240 km in the same time as he convered the 80 km, then this is how you solve it:
80 km in 1.25 hour
240 km in 1.25 hour
Total distance: 80 km + 240 km = 320 km
Total time: 1.25 hour + 1.25 hour = 2.5 hour
average speed = (total distance)/(total time) = 320 km / 2.5 hour = 128 km/h
If it means he covered the 240 km in the same time he covered the 80 km plus the rest, then this is how you solve it:
80 km in 1.25 hour
240 km in 1.25 hour + 45 min = 240 km in 1.25 houir + 0.75 hour = 240 km in 2 hour
Total distance: 80 km + 240 km = 320 km
Total time: 1.25 hour + 2 hour = 3.25 hour
average speed = (total distance)/(total time) = 320 km / 3.25 hour = 98.5 km/h