Finding the Fourth Proportional to 1,407.68, 1,942.40 and 818.08

Step by Step Solution

1. Step 1: Write the proportion equation
   1,407.68 : 1,942.40 = 818.08 : x
2. Step 2: Convert to fraction form
   1,407.68/1,942.40 = 818.08/x
3. Step 3: Cross multiply
   1,407.68x = 1,942.40 × 818.08
4. Step 4: Simplify right side
   1,407.68x = 1,589,038.59
5. Step 5: Solve for x
   x = 1,589,038.59/1,407.68
6. Step 6: Final answer
   x = 1,128.84