Finding the Fourth Proportional to 6,428.64, 8,871.78 and 3,775.92

Step by Step Solution

1. Step 1: Write the proportion equation
   6,428.64 : 8,871.78 = 3,775.92 : x
2. Step 2: Convert to fraction form
   6,428.64/8,871.78 = 3,775.92/x
3. Step 3: Cross multiply
   6,428.64x = 8,871.78 × 3,775.92
4. Step 4: Simplify right side
   6,428.64x = 33,499,131.54
5. Step 5: Solve for x
   x = 33,499,131.54/6,428.64
6. Step 6: Final answer
   x = 5,210.92