Finding the Fourth Proportional to 1,399.95, 1,931.73 and 810.51

Step by Step Solution

1. Step 1: Write the proportion equation
   1,399.95 : 1,931.73 = 810.51 : x
2. Step 2: Convert to fraction form
   1,399.95/1,931.73 = 810.51/x
3. Step 3: Cross multiply
   1,399.95x = 1,931.73 × 810.51
4. Step 4: Simplify right side
   1,399.95x = 1,565,686.48
5. Step 5: Solve for x
   x = 1,565,686.48/1,399.95
6. Step 6: Final answer
   x = 1,118.39