Finding the Fourth Proportional to 30,456.72, 45,708.16 and 12,938.84

Step by Step Solution

1. Step 1: Write the proportion equation
   30,456.72 : 45,708.16 = 12,938.84 : x
2. Step 2: Convert to fraction form
   30,456.72/45,708.16 = 12,938.84/x
3. Step 3: Cross multiply
   30,456.72x = 45,708.16 × 12,938.84
4. Step 4: Simplify right side
   30,456.72x = 591,410,568.93
5. Step 5: Solve for x
   x = 591,410,568.93/30,456.72
6. Step 6: Final answer
   x = 19,418.07