Finding the Fourth Proportional to 21,931.10, 30,264.99 and 12,499.82

Step by Step Solution

1. Step 1: Write the proportion equation
   21,931.10 : 30,264.99 = 12,499.82 : x
2. Step 2: Convert to fraction form
   21,931.10/30,264.99 = 12,499.82/x
3. Step 3: Cross multiply
   21,931.10x = 30,264.99 × 12,499.82
4. Step 4: Simplify right side
   21,931.10x = 378,306,927.30
5. Step 5: Solve for x
   x = 378,306,927.30/21,931.10
6. Step 6: Final answer
   x = 17,249.79