Finding the Fourth Proportional to 1,390.93, 1,919.37 and 801.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,390.93 : 1,919.37 = 801.34 : x
2. Step 2: Convert to fraction form
   1,390.93/1,919.37 = 801.34/x
3. Step 3: Cross multiply
   1,390.93x = 1,919.37 × 801.34
4. Step 4: Simplify right side
   1,390.93x = 1,538,067.96
5. Step 5: Solve for x
   x = 1,538,067.96/1,390.93
6. Step 6: Final answer
   x = 1,105.78