Answer:
9/4
Step-by-step explanation:
The divide symbol is also the line that separates the numerator and the denominator, so 45÷20 can also be written as 45/20.
We can see that both 45 and 20 are divisible by 5, so we can simplify the fraction down to 9x5/4x5, and then we cancel out the 5s and are left with 9/4
Answer:
She needs to sample 189 trees.
Step-by-step explanation:
We have that to find our 
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of 
.
That is z with a pvalue of 
, so Z = 1.96.
Now, find the margin of error M as such
In which 
is the standard deviation of the population and n is the size of the sample.
The standard deviation of the population is 70 peaches per tree.
This means that 
How many trees does she need to sample to obtain an average accurate to within 10 peaches per tree?
She needs to sample n trees.
n is found when M = 10. So
Dividing both sides by 10:
Rounding up:
She needs to sample 189 trees.
Answer:
288
Step-by-step explanation:
This is not a polynomial equation unless one of those is squared. As it stands x=-.833. If you can tell me which is squared I can help solve the polynomial.
Ok, that is usually notated as x^3 to be clear. I'll solve it now.
x^3-13x-12=0
Then use factor theorum to solve x^3-13x-12/x+1 =0
So you get one solution of x+1=0
x=-1
Then you have x^2-x-12 now you complete the square.
Take half of the x-term coefficient and square it. Add this value to both sides. In this example we have:
The x-term coefficient = −1
The half of the x-term coefficient = −1/2
After squaring we have (−1/2)2=1/4
When we add 1/4 to both sides we have:
x2−x+1/4=12+1/4
STEP 3: Simplify right side
x2−x+1/4=49/4
STEP 4: Write the perfect square on the left.
<span>(x−1/2)2=<span>49/4
</span></span>
STEP 5: Take the square root of both sides.
x−1/2=±√49/4
STEP 6: Solve for x.
<span>x=1/2±</span>√49/4
that is,
<span>x1=−3</span>
<span>x2=4</span>
<span>and the one from before </span>
<span>x=-1</span>
