Finding the Fourth Proportional to 33,419.88, 50,139.72 and 12,645

Step by Step Solution

1. Step 1: Write the proportion equation
   33,419.88 : 50,139.72 = 12,645 : x
2. Step 2: Convert to fraction form
   33,419.88/50,139.72 = 12,645/x
3. Step 3: Cross multiply
   33,419.88x = 50,139.72 × 12,645
4. Step 4: Simplify right side
   33,419.88x = 634,016,759.40
5. Step 5: Solve for x
   x = 634,016,759.40/33,419.88
6. Step 6: Final answer
   x = 18,971.25