Finding the Fourth Proportional to 22,491.95, 31,038.73 and 12,420.30

Step by Step Solution

1. Step 1: Write the proportion equation
   22,491.95 : 31,038.73 = 12,420.30 : x
2. Step 2: Convert to fraction form
   22,491.95/31,038.73 = 12,420.30/x
3. Step 3: Cross multiply
   22,491.95x = 31,038.73 × 12,420.30
4. Step 4: Simplify right side
   22,491.95x = 385,510,423.56
5. Step 5: Solve for x
   x = 385,510,423.56/22,491.95
6. Step 6: Final answer
   x = 17,139.93