Finding the Fourth Proportional to 5,086.90, 7,620.78 and 3,987.93

Step by Step Solution

1. Step 1: Write the proportion equation
   5,086.90 : 7,620.78 = 3,987.93 : x
2. Step 2: Convert to fraction form
   5,086.90/7,620.78 = 3,987.93/x
3. Step 3: Cross multiply
   5,086.90x = 7,620.78 × 3,987.93
4. Step 4: Simplify right side
   5,086.90x = 30,391,180.72
5. Step 5: Solve for x
   x = 30,391,180.72/5,086.90
6. Step 6: Final answer
   x = 5,974.40