Minimum required sample size for a desired margin of error and confidence level when it is a proportion problem: n = (z2÷margin of error2)*p-hat*q-hat
The maximum value of p-hat*q-hat occurs where p-hat = .5 (found by taking the derivative of (p-hat)*(1-p-hat) and setting it equal to 0 to find the maximum. n = ( 2.5762( for 99% confidence interval)÷.0482 )*.5*.5 = 720.028 or 721
Answer:
that answer was wrong your dum
Step-by-step explanation:
There is no solution.
To solve it using the substitution method, substitute y from the y = 3x - 4 equation into the 9x - 3y = 14 equation, like so:
9x - 3(3x - 4) = 14
Then after foiling:
9x - 9x -12 = 14
Since there are two x's on the same side, we can just cancel them out leaving:
-12 = 14
Since -12 most definitely does not equal 14, the equation has no solution.
I used this website as a reference: http://www.purplemath.com/modules/systlin4.htm. If it doesn't make sense then you can find some other examples on there that may help you. I hope this helps.
Ratio means a fraction: x to y is x/y.
3x =5y
divide through by y
3x/y = 5
divide through by 3
x/y = 5/3 , or, as a ratio "5 to 3"