Answer:
Step-by-step explanation:
Hypothesis test about a population mean is done to evaluate two exclusive statements about a population in order to determine which is best supported by the sample data.
From the situations given, the correct options are
b. A recent study estimated that 20% of all college students in the United States smoke. The head of Health Services at Goodheart University suspects that the proportion of smokers may be lower there. This would require taking a sample and determining the probability of success.
c. A certain prescription allergy medicine is suppose to contain an average of 245 parts per million (ppm) of active ingredient. The manufacturer wants to check whether the mean concentration in a large shipment of pills is 245 ppm or not.
d. A report on the College Board website stated that in 2003 males scored generally higher than females on the SAT exam. An educational researcher wants to check whether this is true in her school district.
Answer:
880
Step-by-step explanation:
2/5 times 2200
Answer:
Step-by-step explanation:
Let us represent:
Number of children = x = 59
Number of Adults = y = 166
On a certain hot summer's day, 225 people used the public swimming pool.
x + y = 225
x = 225 - y
The daily prices are $1.75 for children and $2.00 for adults. The receipts for admission totaled $435.25.
$1.75 × x + $2.00 × y = $435.25
1.75x + 2y = 435.25
We substitute 225 - y for x
Hence:
1.75(225 - y ) + 2y = 435.25
393.75 - 1.75y + 2y = 435.25
Collect like terms
-1.75y + 2y = 435.25 - 393.75
0.25y = 41.5
y = 41.5/0.25
y = 166 Adults
Note that:
x = 225 - y
x = 225 - 166
x = 59 children
Hence, the number of children is 59 and the number of Adults is 166
Answer:
12
Step-by-step explanation:
(2x-8+2x+10)/2 = 25
(4x+2) = 2×25
4x+2 = 50
4x = 50-2
4x = 48
x = 48/4
x = 12
