Exactly 80 liters of 20% are needed.
Let quantity of 20% alcohol solution be added : x liters
Here is the work:
> x*20% + 40 * 50% = (x+40) * 30%
> x*0.2 + 40*0.5 = (x+40)*0.3 ..(converting percentages into decimal)
> 0.2x + 20 = 0.3x + 12
> 20-12 = 0.3x - 0.2x (Rearranging similar terms)
> 8 = 0.1 x
Hence x = 8/0.1
Ans 80 Litres
The statement that is FALSE among the given options on hypothesis testing is;
Option D; Reducing the significance level (α) can increase a test's effectiveness.
This is about hypothesis testing.
Let us look at each of the options.
- A) When we increase the sample size, it means the testing becomes more sensitive and as such we are more likely to reject the null hypothesis. Thus, it increases the effectiveness.
- B) Alpha (α) is defined as the probability of rejecting the null hypothesis. Thus it is the probability of making a Type I error.
- C) Expanding the sample size makes the hypothesis test to be more sensitive. That is makes it more likely to reject the null hypothesis when it is false and as such it increases the power of the test.
- D) The lower the significance level, the lower the power of the test and as such the lesser the tests effectiveness.
Read more about hypothesis testing at; brainly.com/question/15980493
