Finding the Fourth Proportional to 9,139.46, 12,611.73 and 5,160.96

Step by Step Solution

1. Step 1: Write the proportion equation
   9,139.46 : 12,611.73 = 5,160.96 : x
2. Step 2: Convert to fraction form
   9,139.46/12,611.73 = 5,160.96/x
3. Step 3: Cross multiply
   9,139.46x = 12,611.73 × 5,160.96
4. Step 4: Simplify right side
   9,139.46x = 65,088,634.06
5. Step 5: Solve for x
   x = 65,088,634.06/9,139.46
6. Step 6: Final answer
   x = 7,121.72