Finding the Fourth Proportional to 1,400.40, 1,931.72 and 810.84

Step by Step Solution

1. Step 1: Write the proportion equation
   1,400.40 : 1,931.72 = 810.84 : x
2. Step 2: Convert to fraction form
   1,400.40/1,931.72 = 810.84/x
3. Step 3: Cross multiply
   1,400.40x = 1,931.72 × 810.84
4. Step 4: Simplify right side
   1,400.40x = 1,566,315.84
5. Step 5: Solve for x
   x = 1,566,315.84/1,400.40
6. Step 6: Final answer
   x = 1,118.48