Finding the Fourth Proportional to 13,100.24, 18,078.32 and 7,131.90

Step by Step Solution

1. Step 1: Write the proportion equation
   13,100.24 : 18,078.32 = 7,131.90 : x
2. Step 2: Convert to fraction form
   13,100.24/18,078.32 = 7,131.90/x
3. Step 3: Cross multiply
   13,100.24x = 18,078.32 × 7,131.90
4. Step 4: Simplify right side
   13,100.24x = 128,932,770.41
5. Step 5: Solve for x
   x = 128,932,770.41/13,100.24
6. Step 6: Final answer
   x = 9,842.02