Finding the Fourth Proportional to 1,390.68, 1,919.30 and 801.27

Step by Step Solution

1. Step 1: Write the proportion equation
   1,390.68 : 1,919.30 = 801.27 : x
2. Step 2: Convert to fraction form
   1,390.68/1,919.30 = 801.27/x
3. Step 3: Cross multiply
   1,390.68x = 1,919.30 × 801.27
4. Step 4: Simplify right side
   1,390.68x = 1,537,873.50
5. Step 5: Solve for x
   x = 1,537,873.50/1,390.68
6. Step 6: Final answer
   x = 1,105.84