Finding the Fourth Proportional to 9,386.72, 12,955.28 and 5,407.12

Step by Step Solution

1. Step 1: Write the proportion equation
   9,386.72 : 12,955.28 = 5,407.12 : x
2. Step 2: Convert to fraction form
   9,386.72/12,955.28 = 5,407.12/x
3. Step 3: Cross multiply
   9,386.72x = 12,955.28 × 5,407.12
4. Step 4: Simplify right side
   9,386.72x = 70,050,753.59
5. Step 5: Solve for x
   x = 70,050,753.59/9,386.72
6. Step 6: Final answer
   x = 7,462.75