Finding the Fourth Proportional to 1,387.73, 2,086.05 and 1,116.83

Step by Step Solution

1. Step 1: Write the proportion equation
   1,387.73 : 2,086.05 = 1,116.83 : x
2. Step 2: Convert to fraction form
   1,387.73/2,086.05 = 1,116.83/x
3. Step 3: Cross multiply
   1,387.73x = 2,086.05 × 1,116.83
4. Step 4: Simplify right side
   1,387.73x = 2,329,763.22
5. Step 5: Solve for x
   x = 2,329,763.22/1,387.73
6. Step 6: Final answer
   x = 1,678.83