Finding the Fourth Proportional to 9,403.75, 12,978.12 and 5,212.81

Step by Step Solution

1. Step 1: Write the proportion equation
   9,403.75 : 12,978.12 = 5,212.81 : x
2. Step 2: Convert to fraction form
   9,403.75/12,978.12 = 5,212.81/x
3. Step 3: Cross multiply
   9,403.75x = 12,978.12 × 5,212.81
4. Step 4: Simplify right side
   9,403.75x = 67,652,473.72
5. Step 5: Solve for x
   x = 67,652,473.72/9,403.75
6. Step 6: Final answer
   x = 7,194.20