Answer:
20 +/- $6.74
= ( $13.26, $26.74)
The 90% confidence interval for the difference in average amounts spent on textbooks (math majors - English majors) is ( $13.26, $26.74)
Step-by-step explanation:
Confidence interval can be defined as a range of values so defined that there is a specified probability that the value of a parameter lies within it.
The confidence interval of a statistical data can be written as.
x1-x2 +/- margin of error
x1-x2 +/- z(√(r1^2/n1 + r2^2/n2)
Given that;
Mean x1 = $200
x2 = $180
Standard deviation r1 = $22.50
r2 = $18.30
Number of samples n1 = 60
n2 = 40
Confidence interval = 90%
z(at 90% confidence) = 1.645
Substituting the values we have;
$200-$180 +/-1.645(√(22.5^2/60 +18.3^2/40)
$20 +/- 6.744449847374
$20 +/- $6.74
= ( $13.26, $26.74)
The 90% confidence interval for the difference in average amounts spent on textbooks (math majors - English majors) is ( $13.26, $26.74)
Answer:
The sum of the two numbers is 15
Step-by-step explanation:
Let the counting numbers be x and y.
Then we can write the following equations
x=4y.......1 (one is four times greater )
x(y)=36.....2 (the product of the two)
Putting equation 1 into equation 2, we get
4y(y)=36
Dividing through by 4,we get
Taking square root of both side, we obtain
y=3
Putting the value of y into equation , we get
x=4(3)=12
Hence the numbers are 3 and 12
Therefore the sum of the two numbers is 3+12=15
I can see you come from outside the USA. No insults intended!!
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Anyways, we have to put one side of the ratio and match it to 48.
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Or even better...
.
MAKE!!
A!!
PROPORTION!!
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So... Let's say 7 is proportional to 48... so 7/5 = 48/x, where x is the number equivalent to ratio of 5.
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Cross multiply!!
<span>.
</span>7x = 240.
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Divide 7 on both sides.
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x = 34 2/7.
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Hope I helped!!
Answer:
y= -5/3x-2
Step-by-step explanation:
