Finding the Fourth Proportional to 9,978.06, 14,960.72 and 3,966.78

Step by Step Solution

1. Step 1: Write the proportion equation
   9,978.06 : 14,960.72 = 3,966.78 : x
2. Step 2: Convert to fraction form
   9,978.06/14,960.72 = 3,966.78/x
3. Step 3: Cross multiply
   9,978.06x = 14,960.72 × 3,966.78
4. Step 4: Simplify right side
   9,978.06x = 59,345,884.88
5. Step 5: Solve for x
   x = 59,345,884.88/9,978.06
6. Step 6: Final answer
   x = 5,947.64