Finding the Fourth Proportional to 1,390.37, 1,918.71 and 800.96

Step by Step Solution

1. Step 1: Write the proportion equation
   1,390.37 : 1,918.71 = 800.96 : x
2. Step 2: Convert to fraction form
   1,390.37/1,918.71 = 800.96/x
3. Step 3: Cross multiply
   1,390.37x = 1,918.71 × 800.96
4. Step 4: Simplify right side
   1,390.37x = 1,536,800.37
5. Step 5: Solve for x
   x = 1,536,800.37/1,390.37
6. Step 6: Final answer
   x = 1,105.32