There are 48 available subjects. Researchers should select 4 of them for their experiment.
We should find the number of possible different random samples. The order of the selected subjects is not important. This means that we need to find how many different combinations of subjects from total 48 are possible. <span>A </span>formula<span> for the number of possible </span>combinations<span> of </span>r<span> objects from a </span>set<span> of </span>n<span> objects is: n!/r!(n-r)!. In our case n=48 and r=4:
C=48!/44!*4!=48*47*46*45*44!/44!*4!=</span><span>48*47*46*45/4*3*2*1=4669920/24=
194580.</span>
X = 2.
Set up your equation like this:
3x + 4x = 14
7x = 14
x = 2
Hope this helped
Answer:

its down 1 over 2 each time
Answer:
r = 15
Step-by-step explanation:
10(8r + 23) = 1430
Divide both sides by 10.
8r + 23 = 143
Subtract 23 from both sides.
8r = 120
Divide both sides by 8.
r = 15