Finding the Fourth Proportional to 9,139.24, 12,611.46 and 5,159.80

Step by Step Solution

1. Step 1: Write the proportion equation
   9,139.24 : 12,611.46 = 5,159.80 : x
2. Step 2: Convert to fraction form
   9,139.24/12,611.46 = 5,159.80/x
3. Step 3: Cross multiply
   9,139.24x = 12,611.46 × 5,159.80
4. Step 4: Simplify right side
   9,139.24x = 65,072,611.31
5. Step 5: Solve for x
   x = 65,072,611.31/9,139.24
6. Step 6: Final answer
   x = 7,120.13