Finding the Fourth Proportional to 7,155.20, 9,874.20 and 3,968.72

Step by Step Solution

1. Step 1: Write the proportion equation
   7,155.20 : 9,874.20 = 3,968.72 : x
2. Step 2: Convert to fraction form
   7,155.20/9,874.20 = 3,968.72/x
3. Step 3: Cross multiply
   7,155.20x = 9,874.20 × 3,968.72
4. Step 4: Simplify right side
   7,155.20x = 39,187,935.02
5. Step 5: Solve for x
   x = 39,187,935.02/7,155.20
6. Step 6: Final answer
   x = 5,476.85