Answer:
3
Step-by-step explanation:
f(x) = 2x-5
substitute 4 in for x
f(4) = 2*4 -5
f(4) = 8-5
f(4) =3
Answer:
The test to be used is <em>paired t-test</em>.
Step-by-step explanation:
The dependent <em>t</em>-test (also known as the paired t-test or paired-samples t-test) compares the two means of associated groups to conclude if there is a statistically significant difference between the two means.
We use the paired <em>t</em>-test if we have two measurements on the same item, person or thing. We should also use this test if we have two items that are being measured with a unique condition.
For instance, an experimenter tests the effect of a medicine on a group of patients before and after giving the doses.
The assumptions made to perform a paired <em>t</em>-test are:
- The data are not discreet
.
- The data i.e., the difference, follows a normal distribution
.
- Each individual from the whole population has a same possibility of being selected.
In this case, a random sample of 30 students were selected.
Each student was asked to memorize two different lists of 20 words within 10 minutes, once with music and once without music.
The mean difference in the number of words recalled in both the sets (1: with music, 2: without music) was recorded.
The experiment performed was a matched pair experiment and a paired <em>t</em>-test would be used to perform the analysis to determine whether listening to music while studying hinder students’ learning.
it’s 60 cm^2 because you multiply base times height then divide by 2.
Answer: BC is 9 units long
==============================================================
Work Shown:
Let x be the length of segment BC.
BC is parallel to DE, so this means that triangle ABC is similar to triangle ADE.
Side AB pairs with side AD (both are horizontal sides of triangle ABC and triangle ADE respectively)
Side BC pairs with side DE (both are vertical sides of triangle ABC and triangle ADE respectively)
Because of those facts above, we can end up with this proportion
AB/AD = BC/DE
-------------------
Let's plug in the given values and isolate x
AB/AD = BC/DE
12/20 = x/15
12*15 = 20*x ... cross multiply
180 = 20x
20x = 180
20x/20 = 180/20 ... divide both sides by 20
x = 9
Segment BC is 9 units long.
note: There is no need to calculate the length of segment AE. Though you are correct in stating that AE = 25.
I don't quite understand yet, but I think you have to count the squares on the line between the letters. Does this help?