Do cross multiplication
<u>6</u> = <u>x</u>
18 12
Now cross multiply
(6)(12) = (18)(x)
72 = 18x
Divide both sides by 18
<u>72</u> = <u>18x</u>
18 18
4 = x
So tMei can complete 4 problems in 12 minutes.
Answer:
A) Yes
B) No
C) No
D) No
Step-by-step explanation:
A) Yes, every telephone number that could occur in that community will have an equal chance of being generated because the telephone numbers were generated randomly.
B) No, this method of generating telephone numbers would not result in a simple random sample (SRS) of local residences because the first three digits were generated in a different random way than the last four digits.
C) No, this method would not generate an SRS of local voters because not everybody will be pick up when they call because they may not be at home or they may be too busy to pick up.
D) No, this method is not unbiased in generating samples of households because there will be nonresponse bias since not everyone will pick up the call
Set up a proportion: 25/100 = 50/n where n = # of teens surveyed
Simplify fraction: 1/4 = 50/n
Cross multiply: n = 200
So 200 teens were surveyed.
The answer is A endurance
