Finding the Fourth Proportional to 13,121.93, 19,665.27 and 7,189.89

Step by Step Solution

1. Step 1: Write the proportion equation
   13,121.93 : 19,665.27 = 7,189.89 : x
2. Step 2: Convert to fraction form
   13,121.93/19,665.27 = 7,189.89/x
3. Step 3: Cross multiply
   13,121.93x = 19,665.27 × 7,189.89
4. Step 4: Simplify right side
   13,121.93x = 141,391,128.12
5. Step 5: Solve for x
   x = 141,391,128.12/13,121.93
6. Step 6: Final answer
   x = 10,775.18