Answer: 30%
Step-by-step explanation:
Given : Patient has a 2500 cc bag of irrigation solution hanging.
Irrigation has been infused = 750cc
Then, the percentage of irrigation solution has been infused :

Hence, the percentage of irrigation solution has been infused = 30%
That would be :
4x – 10 = x2 – 5x + 10 ( y = 4x - 10 is substitute for y)
PROOF: y + 5x = x²<span> + 10
</span> (4x - 10) + 5x = x² + 10
4x - 10 = x² -5x + 10
<span>
</span>0 = x2 – 9x + 20<span> (liked terms are grouped and simplified)
PROOF: </span> 4x - 10 = x² -5x + 10
4x = x² -5x + 10 + 10
0 = x² -5x -4x + 20
0 = x² - 9x + 20
Solving:
x² - 9x + 20 = 0
x² - 5x - 4x + 20 = 0
(x - 5) (x - 4) = 0
⇒ x = 4 (as question says) OR x = 5
Since we are not given any information about the proportion, we will assume the sample proportion to be 0.50
so,
p = 0.50
The Error is 10% percentage point. This means that on either side of the population proportion the error is 5% so E = 0.05
z = 1.645 (Z value for 90% confidence interval)
The margin of error for population proportion is calculated as:
This means 271 students should be included in the sample
2) -6
8 is positive and 14 negative. You can either draw a number line and help yourself with that or since the negative one is bigger you can do the subtraction 14 - 8 and then change the sign of the answer.