Finding the Fourth Proportional to 3,859.77, 5,780.42 and 3,666.02

Step by Step Solution

1. Step 1: Write the proportion equation
   3,859.77 : 5,780.42 = 3,666.02 : x
2. Step 2: Convert to fraction form
   3,859.77/5,780.42 = 3,666.02/x
3. Step 3: Cross multiply
   3,859.77x = 5,780.42 × 3,666.02
4. Step 4: Simplify right side
   3,859.77x = 21,191,088.10
5. Step 5: Solve for x
   x = 21,191,088.10/3,859.77
6. Step 6: Final answer
   x = 5,490.25