Finding the Fourth Proportional to 1,405.89, 1,939.33 and 816.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.89 : 1,939.33 = 816.34 : x
2. Step 2: Convert to fraction form
   1,405.89/1,939.33 = 816.34/x
3. Step 3: Cross multiply
   1,405.89x = 1,939.33 × 816.34
4. Step 4: Simplify right side
   1,405.89x = 1,583,152.65
5. Step 5: Solve for x
   x = 1,583,152.65/1,405.89
6. Step 6: Final answer
   x = 1,126.09