Finding the Fourth Proportional to 22,492.61, 31,038.77 and 12,420.57

Step by Step Solution

1. Step 1: Write the proportion equation
   22,492.61 : 31,038.77 = 12,420.57 : x
2. Step 2: Convert to fraction form
   22,492.61/31,038.77 = 12,420.57/x
3. Step 3: Cross multiply
   22,492.61x = 31,038.77 × 12,420.57
4. Step 4: Simplify right side
   22,492.61x = 385,519,066.12
5. Step 5: Solve for x
   x = 385,519,066.12/22,492.61
6. Step 6: Final answer
   x = 17,139.81