Answer :

To solve for the value of [tex]\( x \)[/tex] in the given list of numbers [tex]\( 20, 30, \frac{3x + 5}{2}, 50, 60 \)[/tex] where the median is 40, follow these steps:

1. Identify the Median Position: Since the list has 5 numbers, the median is the middle number. Therefore, the median here is the value at the third position in the list, which is [tex]\(\frac{3x + 5}{2}\)[/tex].

2. Set the Median Equal to 40: According to the problem, the median value is given as 40. Hence we set up the equation:
[tex]\[ \frac{3x + 5}{2} = 40 \][/tex]

3. Solve the Equation:
- First, eliminate the fraction by multiplying both sides of the equation by 2:
[tex]\[ 2 \times \frac{3x + 5}{2} = 40 \times 2 \][/tex]
Simplifying this gives:
[tex]\[ 3x + 5 = 80 \][/tex]

- Next, isolate [tex]\( 3x \)[/tex] by subtracting 5 from both sides:
[tex]\[ 3x = 80 - 5 \][/tex]
Simplifying this gives:
[tex]\[ 3x = 75 \][/tex]

- Finally, solve for [tex]\( x \)[/tex] by dividing both sides by 3:
[tex]\[ x = \frac{75}{3} \][/tex]
Simplifying this gives:
[tex]\[ x = 25 \][/tex]

Therefore, the value of [tex]\( x \)[/tex] is [tex]\( \boxed{25} \)[/tex].