A rational number is a number that can be written as a ratio. That means that it can be written as a fraction. The numerator and the denominator both need to be whole numbers for it to be rational. For example, 2 is a rational number because it can be written as the fraction 2/1.
3x - 5 + 2x = 15+ 4x - 5
5x - 5 = 10 + 4x
5x - 5 + 5 = 10 +5 +4x
5x = 4X + 15
5x - 4x = 4x - 4x + 15
x = 15
Answer:
B
Step-by-step explanation:
There are, 20475 different groups are possible if the manager wants to select one group of 4 people from his 28 assistants.
<h3>What is permutation and combination?</h3>
A permutation is the number of different ways a set can be organized; order matters in permutations, but not in combinations.
We have:
A manager wants to select one group of 4 people from his 28 assistants.
The total number of groups possible = C(28, 4)

After calculating:
= 20475
Thus, there are, 20475 different groups are possible if the manager wants to select one group of 4 people from his 28 assistants.
Learn more about permutation and combination here:
brainly.com/question/2295036
#SPJ1