Finding the Fourth Proportional to 5,865.80, 8,089.40 and 3,980.12

Step by Step Solution

1. Step 1: Write the proportion equation
   5,865.80 : 8,089.40 = 3,980.12 : x
2. Step 2: Convert to fraction form
   5,865.80/8,089.40 = 3,980.12/x
3. Step 3: Cross multiply
   5,865.80x = 8,089.40 × 3,980.12
4. Step 4: Simplify right side
   5,865.80x = 32,196,762.83
5. Step 5: Solve for x
   x = 32,196,762.83/5,865.80
6. Step 6: Final answer
   x = 5,488.90