Finding the Fourth Proportional to 20,868.58, 28,781.89 and 18,345.34

Step by Step Solution

1. Step 1: Write the proportion equation
   20,868.58 : 28,781.89 = 18,345.34 : x
2. Step 2: Convert to fraction form
   20,868.58/28,781.89 = 18,345.34/x
3. Step 3: Cross multiply
   20,868.58x = 28,781.89 × 18,345.34
4. Step 4: Simplify right side
   20,868.58x = 528,013,466.17
5. Step 5: Solve for x
   x = 528,013,466.17/20,868.58
6. Step 6: Final answer
   x = 25,301.84