Finding the Fourth Proportional to 31,131.57, 42,966.38 and 18,386.13

Step by Step Solution

1. Step 1: Write the proportion equation
   31,131.57 : 42,966.38 = 18,386.13 : x
2. Step 2: Convert to fraction form
   31,131.57/42,966.38 = 18,386.13/x
3. Step 3: Cross multiply
   31,131.57x = 42,966.38 × 18,386.13
4. Step 4: Simplify right side
   31,131.57x = 789,985,356.38
5. Step 5: Solve for x
   x = 789,985,356.38/31,131.57
6. Step 6: Final answer
   x = 25,375.70