The factorial ! just means we multiply by every natural number less that the value so
6! =6×5×4×3×2×1= 720
for permutations we use the formula n!/(n-r)!
so we have 8!/(8-5)!=8!/3!=8×7×6×5×4
for combinations s we have n!/(n-r)!r!
so we have 12!/(12-4)!4!=12!/8!4!=12×11×10×9/4×3×2=11×10×9/2=99×5
The correct answer is a (8^3) because you write out 8 being multiplied 3 times, which is the correct answer
N=25 because 20 divided by 4 is 5 which is 1/5 of n meaning 5x5 is 25
The correlation coefficient between two variables, r, is always going to be between -1 and 1.
- If the correlation coefficient is 0, means that there is no strong correlation relationship in one direction or the other direction.
- If the correlation coefficient is -1, means that these two variables move in opposite directions.
- If the correlation coefficient is 1, means that these two variables move in the same direction.