Answer:
Approximately, the 90% confidence interval for the students' mean IQ score is between 129.045 - 130.956
Step-by-step explanation:
The formula to use to solve this question is called the Confidence Interval formula.
Confidence interval =
x ± z × ( σ/ (√n) )
Where:
x = the sample mean = 130
z = the z-value for 90% confidence = 1.645
σ = standard deviation = 7
n = sample size = 145
130 ± 1.645 × (7/√145)
130 ± 0.9562687005
130 - 0.9562687005 = 129.0437313
130 + 0.9562687005 = 130.9562687005
Therefore, approximately, the 90% confidence interval for the students' mean IQ score is between 129.045 - 130.956
Answer:
The chicken which is sold for 5 boxes for 25.50 is better priced.
Step-by-step explanation:
If you buy five boxes of the chicken from the place where it is 5.50 a box, buying five will be 27.50, which costs more than the place with the 25.50 price for five boxes.
Answer:
the arrow :)
Step-by-step explanation:
Keith started with 44 cards.
So we need to work backwards.
After his dog ate half his collection, he had 25 cards.
To reverse that, you need to multiply 25 by 2.
25×2=50
If he bought 6 new cards that day, then he started with 6 cards less.
So you have to subtract 6 from 50.
50-6=44
♡ Hope this helped! ♡
❀ 0ranges ❀
