Finding the Fourth Proportional to 1,329.89, 1,995.10 and 405.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,329.89 : 1,995.10 = 405.50 : x
2. Step 2: Convert to fraction form
   1,329.89/1,995.10 = 405.50/x
3. Step 3: Cross multiply
   1,329.89x = 1,995.10 × 405.50
4. Step 4: Simplify right side
   1,329.89x = 809,002.06
5. Step 5: Solve for x
   x = 809,002.06/1,329.89
6. Step 6: Final answer
   x = 608.32