Finding the Fourth Proportional to 1,388.55, 1,916.45 and 829.06

Step by Step Solution

1. Step 1: Write the proportion equation
   1,388.55 : 1,916.45 = 829.06 : x
2. Step 2: Convert to fraction form
   1,388.55/1,916.45 = 829.06/x
3. Step 3: Cross multiply
   1,388.55x = 1,916.45 × 829.06
4. Step 4: Simplify right side
   1,388.55x = 1,588,847.89
5. Step 5: Solve for x
   x = 1,588,847.89/1,388.55
6. Step 6: Final answer
   x = 1,144.25