Answer:
The critical value of <em>t</em> at 0.01 level of significance is 2.66.
Step-by-step explanation:
The hypothesis for the two-tailed population mean can be defined as:
<em>H₀</em>: <em>μ </em>= <em>μ₀</em> vs. <em>H₀</em>: <em>μ </em>≠ <em>μ₀</em>
It is provided that the population standard deviation is not known.
Since there is no information about the population standard deviation, we will use a <em>t</em>-test for single mean.
The test statistic is defined as follows:

The information given is:
<em>n</em> = 55
<em>α</em> =<em> </em>0.01
Compute the critical value of <em>t</em> as follows:

*Use a <em>t</em>-table for the value.
If the desired degrees of freedom are not provided consider he next highest degree of freedom.
Thus, the critical value of <em>t</em> at 0.01 level of significance is 2.66.
The ratio of the length of the room to its area is
1,4(0,5x + 4,2y) - 3,5(0,2x - 1,5y)
1,4.0,5x + 1,4.4,2y - 3,5.0,2x + 3,5.1,5y
0,7x + 5,88y - 0,7x + 5,25y
0,7x - 0,7x + 5,88y + 5,25y
11,13y
How many 6-digit numbers can be formed using the digits 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, if repetitions of digits are allowed?
sveta [45]
There are 6 digits. Each digit can take ten different numbers except for the first digit since it cannot be zero.
So:
9 x 10 x 10 x 10 x 10 x 10
900000 numbers.
Another way of thinking about this is to just count up to 999,999. Obviously there are 999,999 different numbers here. But since our number has to have 6 digits in them, we have to delete 99,999 numbers. Thus there are 900,000 different numbers.