Finding the Fourth Proportional to 1,388.04, 1,916.82 and 864.24

Step by Step Solution

1. Step 1: Write the proportion equation
   1,388.04 : 1,916.82 = 864.24 : x
2. Step 2: Convert to fraction form
   1,388.04/1,916.82 = 864.24/x
3. Step 3: Cross multiply
   1,388.04x = 1,916.82 × 864.24
4. Step 4: Simplify right side
   1,388.04x = 1,656,592.52
5. Step 5: Solve for x
   x = 1,656,592.52/1,388.04
6. Step 6: Final answer
   x = 1,193.48