Finding the Fourth Proportional to 1,387.10, 1,913.82 and 827.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,387.10 : 1,913.82 = 827.31 : x
2. Step 2: Convert to fraction form
   1,387.10/1,913.82 = 827.31/x
3. Step 3: Cross multiply
   1,387.10x = 1,913.82 × 827.31
4. Step 4: Simplify right side
   1,387.10x = 1,583,322.42
5. Step 5: Solve for x
   x = 1,583,322.42/1,387.10
6. Step 6: Final answer
   x = 1,141.47