Finding the Fourth Proportional to 1,395.28, 1,925.40 and 805.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,395.28 : 1,925.40 = 805.72 : x
2. Step 2: Convert to fraction form
   1,395.28/1,925.40 = 805.72/x
3. Step 3: Cross multiply
   1,395.28x = 1,925.40 × 805.72
4. Step 4: Simplify right side
   1,395.28x = 1,551,333.29
5. Step 5: Solve for x
   x = 1,551,333.29/1,395.28
6. Step 6: Final answer
   x = 1,111.84