Finding the Fourth Proportional to 30,105.12, 45,139.86 and 12,330.48

Step by Step Solution

1. Step 1: Write the proportion equation
   30,105.12 : 45,139.86 = 12,330.48 : x
2. Step 2: Convert to fraction form
   30,105.12/45,139.86 = 12,330.48/x
3. Step 3: Cross multiply
   30,105.12x = 45,139.86 × 12,330.48
4. Step 4: Simplify right side
   30,105.12x = 556,596,140.93
5. Step 5: Solve for x
   x = 556,596,140.93/30,105.12
6. Step 6: Final answer
   x = 18,488.42