Finding the Fourth Proportional to 13,123.64, 18,110.29 and 7,155.42

Step by Step Solution

1. Step 1: Write the proportion equation
   13,123.64 : 18,110.29 = 7,155.42 : x
2. Step 2: Convert to fraction form
   13,123.64/18,110.29 = 7,155.42/x
3. Step 3: Cross multiply
   13,123.64x = 18,110.29 × 7,155.42
4. Step 4: Simplify right side
   13,123.64x = 129,586,780.88
5. Step 5: Solve for x
   x = 129,586,780.88/13,123.64
6. Step 6: Final answer
   x = 9,874.30