Finding the Fourth Proportional to 13,099.69, 18,077.54 and 7,131.40

Step by Step Solution

1. Step 1: Write the proportion equation
   13,099.69 : 18,077.54 = 7,131.40 : x
2. Step 2: Convert to fraction form
   13,099.69/18,077.54 = 7,131.40/x
3. Step 3: Cross multiply
   13,099.69x = 18,077.54 × 7,131.40
4. Step 4: Simplify right side
   13,099.69x = 128,918,114.65
5. Step 5: Solve for x
   x = 128,918,114.65/13,099.69
6. Step 6: Final answer
   x = 9,841.31