Finding the Fourth Proportional to 8,320.76, 12,478.08 and 3,387.72

Step by Step Solution

1. Step 1: Write the proportion equation
   8,320.76 : 12,478.08 = 3,387.72 : x
2. Step 2: Convert to fraction form
   8,320.76/12,478.08 = 3,387.72/x
3. Step 3: Cross multiply
   8,320.76x = 12,478.08 × 3,387.72
4. Step 4: Simplify right side
   8,320.76x = 42,272,300.67
5. Step 5: Solve for x
   x = 42,272,300.67/8,320.76
6. Step 6: Final answer
   x = 5,080.34