Finding the Fourth Proportional to 1,390.24, 1,917.86 and 800.44

Step by Step Solution

1. Step 1: Write the proportion equation
   1,390.24 : 1,917.86 = 800.44 : x
2. Step 2: Convert to fraction form
   1,390.24/1,917.86 = 800.44/x
3. Step 3: Cross multiply
   1,390.24x = 1,917.86 × 800.44
4. Step 4: Simplify right side
   1,390.24x = 1,535,131.86
5. Step 5: Solve for x
   x = 1,535,131.86/1,390.24
6. Step 6: Final answer
   x = 1,104.22