Finding the Fourth Proportional to 13,638.85, 18,820.56 and 7,669.33

Step by Step Solution

1. Step 1: Write the proportion equation
   13,638.85 : 18,820.56 = 7,669.33 : x
2. Step 2: Convert to fraction form
   13,638.85/18,820.56 = 7,669.33/x
3. Step 3: Cross multiply
   13,638.85x = 18,820.56 × 7,669.33
4. Step 4: Simplify right side
   13,638.85x = 144,341,085.42
5. Step 5: Solve for x
   x = 144,341,085.42/13,638.85
6. Step 6: Final answer
   x = 10,583.08