Finding the Fourth Proportional to 21,145.98, 31,738.41 and 19,875.90

Step by Step Solution

1. Step 1: Write the proportion equation
   21,145.98 : 31,738.41 = 19,875.90 : x
2. Step 2: Convert to fraction form
   21,145.98/31,738.41 = 19,875.90/x
3. Step 3: Cross multiply
   21,145.98x = 31,738.41 × 19,875.90
4. Step 4: Simplify right side
   21,145.98x = 630,829,463.32
5. Step 5: Solve for x
   x = 630,829,463.32/21,145.98
6. Step 6: Final answer
   x = 29,832.12