Finding the Fourth Proportional to 2,086.86, 3,130.32 and 991.34

Step by Step Solution

1. Step 1: Write the proportion equation
   2,086.86 : 3,130.32 = 991.34 : x
2. Step 2: Convert to fraction form
   2,086.86/3,130.32 = 991.34/x
3. Step 3: Cross multiply
   2,086.86x = 3,130.32 × 991.34
4. Step 4: Simplify right side
   2,086.86x = 3,103,195.78
5. Step 5: Solve for x
   x = 3,103,195.78/2,086.86
6. Step 6: Final answer
   x = 1,487.02