Finding the Fourth Proportional to 9,139.86, 12,613.50 and 5,161.14

Step by Step Solution

1. Step 1: Write the proportion equation
   9,139.86 : 12,613.50 = 5,161.14 : x
2. Step 2: Convert to fraction form
   9,139.86/12,613.50 = 5,161.14/x
3. Step 3: Cross multiply
   9,139.86x = 12,613.50 × 5,161.14
4. Step 4: Simplify right side
   9,139.86x = 65,100,039.39
5. Step 5: Solve for x
   x = 65,100,039.39/9,139.86
6. Step 6: Final answer
   x = 7,122.65