Finding the Fourth Proportional to 1,407.76, 1,942.71 and 818.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,407.76 : 1,942.71 = 818.31 : x
2. Step 2: Convert to fraction form
   1,407.76/1,942.71 = 818.31/x
3. Step 3: Cross multiply
   1,407.76x = 1,942.71 × 818.31
4. Step 4: Simplify right side
   1,407.76x = 1,589,739.02
5. Step 5: Solve for x
   x = 1,589,739.02/1,407.76
6. Step 6: Final answer
   x = 1,129.27