Finding the Fourth Proportional to 1,386.38, 1,913.15 and 756.90

Step by Step Solution

1. Step 1: Write the proportion equation
   1,386.38 : 1,913.15 = 756.90 : x
2. Step 2: Convert to fraction form
   1,386.38/1,913.15 = 756.90/x
3. Step 3: Cross multiply
   1,386.38x = 1,913.15 × 756.90
4. Step 4: Simplify right side
   1,386.38x = 1,448,049.88
5. Step 5: Solve for x
   x = 1,448,049.88/1,386.38
6. Step 6: Final answer
   x = 1,044.48