Answer:
The perpendicular line 4x − 5y = 20 has a slope of 4/5 and as such, the slope of the required line = -5/4
(y - 3)/(x + 4) = -5/4 simplify to get the required equation: 5x + 4y + 8 = 0
I need more information for this, the y-axis!
If we assume the number of polo shirts have been sold is x, the number of casual shirts have been sold will be 4x.
x*18+4x*9=$1080
(18+36)x=$1080
54x=$1080
x=20
The number of casual shirts have been sold is 4*20=80
Time used for the call to Zurich: ($5-$1.25)/$0.25=15 minutes
15minutes+3minutes=18minutes
Time used for the call to London: ($7.25-$1.25)/$0.25=24 minutes
24minutes+3minutes=27minutes
Difference between the two calls:27-18=9minutes
All our answers lie in the above statement.
Confidence Level:
The creator claims that 9 out 10 students will have the average score in the said range. Or in other words we can say that the creator is 90% confident about the result of the field test. So the confidence level is 90%.
Margin of Error:
The average score lies within 4% of 70%. This means the margin of error is 4% i.e. the average scores can deviate from 70% by 4% .
Confidence Interval:
Lower Limit = 70% - 4% = 66%
Upper Limit = 70% + 4% = 74%
Interpretation:
The exam creator is 90% confident that the average scores of seniors will be between 66% and 74%.
