Finding the Fourth Proportional to 42,018.72, 63,025.86 and 15,721.47

Step by Step Solution

1. Step 1: Write the proportion equation
   42,018.72 : 63,025.86 = 15,721.47 : x
2. Step 2: Convert to fraction form
   42,018.72/63,025.86 = 15,721.47/x
3. Step 3: Cross multiply
   42,018.72x = 63,025.86 × 15,721.47
4. Step 4: Simplify right side
   42,018.72x = 990,859,167.21
5. Step 5: Solve for x
   x = 990,859,167.21/42,018.72
6. Step 6: Final answer
   x = 23,581.37