Finding the Fourth Proportional to 2,618.48, 3,927.82 and 839.90

Step by Step Solution

1. Step 1: Write the proportion equation
   2,618.48 : 3,927.82 = 839.90 : x
2. Step 2: Convert to fraction form
   2,618.48/3,927.82 = 839.90/x
3. Step 3: Cross multiply
   2,618.48x = 3,927.82 × 839.90
4. Step 4: Simplify right side
   2,618.48x = 3,298,976.02
5. Step 5: Solve for x
   x = 3,298,976.02/2,618.48
6. Step 6: Final answer
   x = 1,259.88