Finding the Fourth Proportional to 31,665.18, 43,690.46 and 18,915.86

Step by Step Solution

1. Step 1: Write the proportion equation
   31,665.18 : 43,690.46 = 18,915.86 : x
2. Step 2: Convert to fraction form
   31,665.18/43,690.46 = 18,915.86/x
3. Step 3: Cross multiply
   31,665.18x = 43,690.46 × 18,915.86
4. Step 4: Simplify right side
   31,665.18x = 826,442,624.70
5. Step 5: Solve for x
   x = 826,442,624.70/31,665.18
6. Step 6: Final answer
   x = 26,099.41