Finding the Fourth Proportional to 1,315.78, 1,815.89 and 756.27

Step by Step Solution

1. Step 1: Write the proportion equation
   1,315.78 : 1,815.89 = 756.27 : x
2. Step 2: Convert to fraction form
   1,315.78/1,815.89 = 756.27/x
3. Step 3: Cross multiply
   1,315.78x = 1,815.89 × 756.27
4. Step 4: Simplify right side
   1,315.78x = 1,373,299.35
5. Step 5: Solve for x
   x = 1,373,299.35/1,315.78
6. Step 6: Final answer
   x = 1,043.72