Finding the Fourth Proportional to 3,675.18, 5,540.31 and 3,430.78

Step by Step Solution

1. Step 1: Write the proportion equation
   3,675.18 : 5,540.31 = 3,430.78 : x
2. Step 2: Convert to fraction form
   3,675.18/5,540.31 = 3,430.78/x
3. Step 3: Cross multiply
   3,675.18x = 5,540.31 × 3,430.78
4. Step 4: Simplify right side
   3,675.18x = 19,007,539.89
5. Step 5: Solve for x
   x = 19,007,539.89/3,675.18
6. Step 6: Final answer
   x = 5,171.87