Finding the Fourth Proportional to 1,388.78, 1,916.16 and 829.00

Step by Step Solution

1. Step 1: Write the proportion equation
   1,388.78 : 1,916.16 = 829.00 : x
2. Step 2: Convert to fraction form
   1,388.78/1,916.16 = 829.00/x
3. Step 3: Cross multiply
   1,388.78x = 1,916.16 × 829.00
4. Step 4: Simplify right side
   1,388.78x = 1,588,495.93
5. Step 5: Solve for x
   x = 1,588,495.93/1,388.78
6. Step 6: Final answer
   x = 1,143.81