Answer:
72cm²
Step-by-step explanation:
Hello!
The formula for area of a trapezoid: ![A = \frac12(b_1 + b_2)h](https://tex.z-dn.net/?f=A%20%3D%20%5Cfrac12%28b_1%20%2B%20b_2%29h)
We find the average of the bases, and multiply it by the height.
<h3>Plug in the values and solve</h3>
The area of the trapezoid is 72cm²
Answer:
$8.37
Step-by-step explanation:
2.10 - 0.84 = 1.26
4.50 - 0.84 = 3.66
3.50 - 0.84 = 2.66
2.60- 0.84= 1.76
1.26+3.66+2.66+1.76= 9.34
9.34- 1.50= 7.84
7.84 + 6.75 %= 8.3692 (rounded 8.37)
The mixed number of it would be 5 42/45 if you're looking for the mixed number (to find the mixed number divide 267 and 45)
144, cause each child gets a chocolate and a fruit candy
<h2>
Answer with explanation:</h2>
Let
be the average weight of chocolate chips in each bag.
As per given , we have
![H_0: \mu =439.0\\\\ H_a: \mu](https://tex.z-dn.net/?f=H_0%3A%20%5Cmu%20%3D439.0%5C%5C%5C%5C%20H_a%3A%20%5Cmu%3C439.0)
Since
is left-tailed , so we perform a left-tailed test.
Also, the population standard deviation is known
.
So we use z-test.
Test statistic : ![z=\dfrac{\overline{x}-\mu}{\dfrac{\sigma}{\sqt{n}}}](https://tex.z-dn.net/?f=z%3D%5Cdfrac%7B%5Coverline%7Bx%7D-%5Cmu%7D%7B%5Cdfrac%7B%5Csigma%7D%7B%5Csqt%7Bn%7D%7D%7D)
Substitute given value ,![\overline{x}=433.0\ , n=47,\ \sigma=21 \ , \mu=439](https://tex.z-dn.net/?f=%5Coverline%7Bx%7D%3D433.0%5C%20%2C%20n%3D47%2C%5C%20%5Csigma%3D21%20%5C%20%2C%20%5Cmu%3D439)
![z=\dfrac{433-439}{\dfrac{21}{\sqrt{47}}}\approx-1.96](https://tex.z-dn.net/?f=z%3D%5Cdfrac%7B433-439%7D%7B%5Cdfrac%7B21%7D%7B%5Csqrt%7B47%7D%7D%7D%5Capprox-1.96)
Significance level = 0.05
Decision rule : Reject
when p-value < 0.05.
By z-table , P- value for left-tailed test = P(z<-1.96)= 1- P(z<1.96)
[∵ P(Z<-z)=1-P(Z<z)]
= 1- 0.9750
=0.025
Since , P-value(0.025) < 0.05 , so we reject the null hypothesis.
We support the claim that the machine is underfilling the bags at 0.05 significance level .