Answer:
Step-by-step explanation:
We are given that:
First, we can distribute the right-hand side:
Distribute:
Rewrite:
Since it is equivalent to the above expression, the coefficients of the variables must match. This means that:
Solving for a in the second equation gives:
Therefore:
Title:
<h2>The answer isStep-by-step explanation:
Let the building contractor bought 1000 cement in total.
70% of 1000 = 700 cements were from A and (1000 - 700) = 300 cements were from B.
The number of undamaged bag from A was 95% of 700 = and the number of undamaged bags from B was 70% of 300 =
.
Total undamaged bags were (665 + 210) = 870.
The probability that an undamaged bag is from A is .
Answer:
For α=0.01 and two-tailed test: t=2.8188
For α=0.025 and two-tailed test: t=2.4055
For α=0.05 and two-tailed test: t=2.0739
For α=0.10 and two-tailed test: t=1.7171
Step-by-step explanation:
In this problem, we have to estimate the value of the statistic "t" of a sample of size n=23 (22 degrees of freedom), in which the sample mean is M=770 and the sample standard deviation is s=25.
The estimated standard deviation is
The critical values of the statistic t depends on the significance level:
The degree of freedom is known: df=22.
For α=0.01 and two-tailed test: t=2.8188
For α=0.025 and two-tailed test: t=2.4055
For α=0.05 and two-tailed test: t=2.0739
For α=0.10 and two-tailed test: t=1.7171