Answer:
Thus, 3/2 in, or 1.5 in, represents 1 mile.
Step-by-step explanation:
"3 quarter inches to the half mile" can be expressed as "3/4 inch to 1/2 mile."
Write and solve an equation of ratios to obtain the unit rate in inches/mi:
3/4 in x
---------- = ---------
1/2 mi 1 mi
Cross multiplying, we get 3/4 in-mi = (1/2) mi*x.
Solve this for x by mult. both sides by 2:
6/4 in-mi = x mi
and then dividing both sides by mi:
(6/4) in-mi
--------------- = 3/2 in
mi
Thus, 3/2 in, or 1.5 in, represents 1 mile.
Answer:
Option b) r = 0.70
Step-by-step explanation:
We are given the following in he question:
Variables:
x = the number of hours spent studying for a test
y = the number of points earned on the test
- Correlation is a technique that help us to find or define a relationship between two variables.
- A positive correlation means that an increase in one quantity leads to an increase in another quantity
- A negative correlation means with increase in one quantity the other quantity decreases.
- +1 tells about a a perfect positive linear relationship and −1 indicates a perfect negative linear relationship.
- Values between 0 and 0.3 tells about a weak positive linear relationship, values between 0.3 and 0.7 shows a moderate positive correlation and a correlation of 0.7 and 1.0 states a strong positive linear relationship.
- Values between 0 and -0.3 tells about a weak negative linear relationship, values between -0.3 and -0.7 shows a moderate negative correlation and a correlation value of of -0.7 and -1.0 states a strong negative linear relationship.
As the number of hours increases, the number of points earned on the test increases. Thus, the two variables are positively correlated.
Thus, the coefficient correlation between two variables can be given by r = 0.70, that shows a moderate positive correlation.
Option b) r = 0.70
Answer:
Step-by-step explanation:
Given that n =30, x bar = 375 and sigma = 81
Normal distribution is assumed and population std dev is known
Hence z critical values can be used.
For 95% Z critical=1.96
Margin of error = 
Confidence interval = 375±29
=(346,404)
B) 99% confidence
Margin of error = 2.59*Std error =38
Confidence interval = 375±38
=(337, 413)
C) For 90%
Margin of error = 20
Std error = 20/1.645 = 12.158
Sample size
Atleast 44 people should be sample size.
Answer:
2 quarters and 5 dimes
Step-by-step explanation:
(2) 25 cent coins = 50 cents
(5) 10 cent coins = 50 cents
equals $1
