Finding the Fourth Proportional to 2,086.27, 3,129.53 and 991.69

Step by Step Solution

1. Step 1: Write the proportion equation
   2,086.27 : 3,129.53 = 991.69 : x
2. Step 2: Convert to fraction form
   2,086.27/3,129.53 = 991.69/x
3. Step 3: Cross multiply
   2,086.27x = 3,129.53 × 991.69
4. Step 4: Simplify right side
   2,086.27x = 3,103,523.61
5. Step 5: Solve for x
   x = 3,103,523.61/2,086.27
6. Step 6: Final answer
   x = 1,487.59