1) Proportion a.
7 : 28 = 2 : 8
That means that the ratio 7 / 28 is equal to the ratio 2 : 8.
You can verify the equality by simplifying to the simplest form:
7 : 28 = 1 / 4 simplest form
2 : 8 = 1 / 4 simplest form, then the proportion is right.
In words that is 7 is to 28 as 1 is to 4 ← answer
2) Proportion b.<span>. 3⁄1 = 18⁄6
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</span><span>In words: 3 is to q as 18 is to 6 ← answer
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</span><span>You can verify the proportion by simplifiying the second fraction:
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</span><span> 18 / 6 = [18 / 6] / [ 6 / 6] = 3 / 1
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</span><span>3) Proportion c. 9 : 72 = 2 : 16
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</span><span>In words: 9 is to 72 as 2 is to 16 ← answer
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</span><span>Proove the proportion:
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</span><span> 9 / 72 = 1 / 8
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</span><span> 2 / 16 = 1 / 8
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</span><span>4) Proportion d. 81⁄9 = 45⁄5</span>
In words: 81 is to 9 as 45 is to 5 ← answer
Proove it:
81 / 9 = 9
45 / 9 = 9
Answer:
$25
Step-by-step explanation:
she received$12 five times
12×5=60 ...(1)
she earned$5 two times for yard work
5×2=10....(2)
(1)+(2).... 60+10=70
Bought dog food and ticket
30+15=45
70-45=25
Answer $25 is what she is left with at the end of the month
C) x = -19/10 because when solving it with substitution u get x=-19/10 & y=153/10
Answer:
a. [ 0.454,0.51]
b. 599.472 ~ 600
Step-by-step explanation:
a)
Confidence Interval For Proportion
CI = p ± Z a/2 Sqrt(p*(1-p)/n)))
x = Mean
n = Sample Size
a = 1 - (Confidence Level/100)
Za/2 = Z-table value
CI = Confidence Interval
Mean(x)=410
Sample Size(n)=850
Sample proportion = x/n =0.482
Confidence Interval = [ 0.482 ±Z a/2 ( Sqrt ( 0.482*0.518) /850)]
= [ 0.482 - 1.645* Sqrt(0) , 0.482 + 1.65* Sqrt(0) ]
= [ 0.454,0.51]
b)
Compute Sample Size ( n ) = n=(Z/E)^2*p*(1-p)
Z a/2 at 0.05 is = 1.96
Samle Proportion = 0.482
ME = 0.04
n = ( 1.96 / 0.04 )^2 * 0.482*0.518
= 599.472 ~ 600
Answer:
That's basically how you solve it
