Finding the Fourth Proportional to 2,380.91, 3,285.86 and 1,386.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,380.91 : 3,285.86 = 1,386.50 : x
2. Step 2: Convert to fraction form
   2,380.91/3,285.86 = 1,386.50/x
3. Step 3: Cross multiply
   2,380.91x = 3,285.86 × 1,386.50
4. Step 4: Simplify right side
   2,380.91x = 4,555,821.53
5. Step 5: Solve for x
   x = 4,555,821.53/2,380.91
6. Step 6: Final answer
   x = 1,913.48