Finding the Fourth Proportional to 1,423.89, 1,964.39 and 864.09

Step by Step Solution

1. Step 1: Write the proportion equation
   1,423.89 : 1,964.39 = 864.09 : x
2. Step 2: Convert to fraction form
   1,423.89/1,964.39 = 864.09/x
3. Step 3: Cross multiply
   1,423.89x = 1,964.39 × 864.09
4. Step 4: Simplify right side
   1,423.89x = 1,697,405.43
5. Step 5: Solve for x
   x = 1,697,405.43/1,423.89
6. Step 6: Final answer
   x = 1,192.09