12k-2+6k
find like terms and put them next to each other
12k+6k-2
combine like terms
18k-2
C
Answer:
26.2% of smokers,when given this treatment, would refrain from smoking for at least 6 months.
Step-by-step explanation:
In this problem, we have that:
935 smokers received the treatment(nicotine patch).
After 6 months, 245 of them were not smoking.
Assuming it is reasonable to regard this sample as representative of all smokers, estimate the percentage of all smokers who, when given this treatment, would refrain from smoking for at least 6 months.
This percentage is 245/935 = 0.2620.
26% of smokers,when given this treatment, would refrain from smoking for at least 6 months.
1-2. The best estimate for the population mean would be sample mean of 60 gallons. Since we know that the sample mean is the best point of estimate. Since sample size n=16 is less than 25, we use the t distribution. Assume population from normal distribution.
3. Given a=0.1, the t (0.05, df = n – 1 = 15)=1.75
4. xbar ± t*s/vn = 60 ± 1.75*20/4 = ( 51.25, 68.75)
5. Since the interval include 63, it is reasonable.
<h3>
Answer: 19 dimes</h3>
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Work Shown:
d = number of dimes
q = 32-d = number of quarters
$5.15 = 515 cents
10d+25q = 515
10d+25(32-d) = 515
10d+800-25d = 515
-15d+800 = 515
-15d = 515-800
-15d = -285
d = -285/(-15)
d = 19
There are 19 dimes. You can stop here if you want.
q = 32-d = 32-19 = 13
There are 13 quarters
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Check:
1 dime = 10 cents
19 dimes = 19*10 = 190 cents
1 quarter = 25 cents
13 quarters = 13*25 = 325 cents
total value = 190 cents + 325 cents = 515 cents = $5.15
The answer is confirmed.
