Finding the Fourth Proportional to 1,407.78, 1,942.61 and 818.37

Step by Step Solution

1. Step 1: Write the proportion equation
   1,407.78 : 1,942.61 = 818.37 : x
2. Step 2: Convert to fraction form
   1,407.78/1,942.61 = 818.37/x
3. Step 3: Cross multiply
   1,407.78x = 1,942.61 × 818.37
4. Step 4: Simplify right side
   1,407.78x = 1,589,769.65
5. Step 5: Solve for x
   x = 1,589,769.65/1,407.78
6. Step 6: Final answer
   x = 1,129.27