Answer :

To solve for the missing numerator in the proportion [tex]\(\frac{?}{108} = \frac{4}{9}\)[/tex], we need to set up an equation and solve for the unknown numerator.

Step 1: Write the proportion as an equation.
[tex]\[ \frac{x}{108} = \frac{4}{9} \][/tex]
where [tex]\(x\)[/tex] is the missing numerator.

Step 2: To solve for [tex]\(x\)[/tex], we can utilize the property of proportions which states that the cross products of the ratios are equal. This means:
[tex]\[ 9x = 108 \times 4 \][/tex]

Step 3: Calculate the right-hand side of the equation:
[tex]\[ 9x = 432 \][/tex]

Step 4: Divide both sides of the equation by 9 to isolate [tex]\(x\)[/tex]:
[tex]\[ x = \frac{432}{9} \][/tex]

Step 5: Perform the division to find [tex]\(x\)[/tex]:
[tex]\[ x = 48 \][/tex]

Therefore, the missing numerator is [tex]\(48\)[/tex].

Given the provided options:
- 90
- 45
- 54
- 48

The correct answer is [tex]\(48\)[/tex].