Finding the Fourth Proportional to 6,113.82, 8,437.20 and 3,990.72

Step by Step Solution

1. Step 1: Write the proportion equation
   6,113.82 : 8,437.20 = 3,990.72 : x
2. Step 2: Convert to fraction form
   6,113.82/8,437.20 = 3,990.72/x
3. Step 3: Cross multiply
   6,113.82x = 8,437.20 × 3,990.72
4. Step 4: Simplify right side
   6,113.82x = 33,670,502.78
5. Step 5: Solve for x
   x = 33,670,502.78/6,113.82
6. Step 6: Final answer
   x = 5,507.28