Finding the Fourth Proportional to 8,340.28, 12,499.98 and 3,407.20

Step by Step Solution

1. Step 1: Write the proportion equation
   8,340.28 : 12,499.98 = 3,407.20 : x
2. Step 2: Convert to fraction form
   8,340.28/12,499.98 = 3,407.20/x
3. Step 3: Cross multiply
   8,340.28x = 12,499.98 × 3,407.20
4. Step 4: Simplify right side
   8,340.28x = 42,589,931.86
5. Step 5: Solve for x
   x = 42,589,931.86/8,340.28
6. Step 6: Final answer
   x = 5,106.54