Answer:
45 mins
Step-by-step explanation:
Isolate the variable, I would add d to both sides, creating 4<4+d+d or 4<4+2d
then subtract 4,
0<2d
d>0
Answer:
C
Step-by-step explanation:
The distance around the circle is asking for the circumference of the circle.
Since we know that the diameter is 21 and the equation for the circumference of a circle is 2*pi*r and since 2*r is just the diameter, we can say that the circumference is 21*pi, which would be C.
Answer:
96
Step-by-step explanation:
<u>Step 1
</u>
Divide your confidence interval by 2. In this case the confidence is 95% = 0.095, so 0.095/2 = 0.0475
<u>Step 2
</u>
Use either a z-score table or a computer to find the closest z-score for 0.0475 and you will find this value is 1.96
<u>Step 3
</u>
Divide the margin error by 2. In this case, the margin error is 2%. When dividing this figure by 2, we get 1% = 0.01
<u>Step 4
</u>
Divide the number obtained in Step 2 by the number obtained in Step 3 and square it
1.96/0.01 = 196 and 196 squared is 38,416
<u>Step 5
</u>
As we do not now a proportion of people that purchase on line, we must assume this value is 50% = 0.5. Square this number and you get 0.25
<u>Step 6
</u>
Multiply the number obtained in Step 5 by the number obtained in Step 4, round it to the nearest integer and this is an appropriate size of the sample.
38,416*0.25 = 9,604
