Answer:
A , D
Step-by-step explanation:
hello :
b= √18 because : (√18)² =18
b= - √18 because : (-√18)² =18
{-2x+y=12 => y=12+2x
{3x+2y=38
3x+2(12+2x)=38
3x+24+4x=38 /-24
7x=14 /:7
x=2
y=12+2*2=12+4=16
y=16
<em>Solution: (2; 16)</em>
<em>
</em>
Answer:
$11.00
Step-by-step explanation:
Since 92 texts cost her 9.20, each text cost her 10 cents. 110*10 =1100
Answer: 709
Step-by-step explanation:
The formulas we use to find the required sample size :-
1.
, where = population standard deviation,
E = Margin of error .
z* = Critical value
2. , where p= prior estimate of population proportion.
3. If prior estimate of population proportion is unavailable , then we take p= 0.5 and the formula becomes
Given : Margin of error : E= 3% =0.03
Critical value for 95% confidence interval = z*= 1.96
A study conducted several years ago revealed that the percent of junior executives leaving within three years was 21%.
i.e. p=0.21
Then by formula 2., the required sample size will be :
[Round to the next integer.]
Hence, the required sample size of junior executives should be studied = 709