Finding the Fourth Proportional to 1,388.91, 1,916.38 and 829.29

Step by Step Solution

1. Step 1: Write the proportion equation
   1,388.91 : 1,916.38 = 829.29 : x
2. Step 2: Convert to fraction form
   1,388.91/1,916.38 = 829.29/x
3. Step 3: Cross multiply
   1,388.91x = 1,916.38 × 829.29
4. Step 4: Simplify right side
   1,388.91x = 1,589,234.55
5. Step 5: Solve for x
   x = 1,589,234.55/1,388.91
6. Step 6: Final answer
   x = 1,144.24