Finding the Fourth Proportional to 42,530.72, 63,805.30 and 12,947.78

Step by Step Solution

1. Step 1: Write the proportion equation
   42,530.72 : 63,805.30 = 12,947.78 : x
2. Step 2: Convert to fraction form
   42,530.72/63,805.30 = 12,947.78/x
3. Step 3: Cross multiply
   42,530.72x = 63,805.30 × 12,947.78
4. Step 4: Simplify right side
   42,530.72x = 826,137,114.38
5. Step 5: Solve for x
   x = 826,137,114.38/42,530.72
6. Step 6: Final answer
   x = 19,424.48