Finding the Fourth Proportional to 1,280.53, 1,921.54 and 540.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,280.53 : 1,921.54 = 540.10 : x
2. Step 2: Convert to fraction form
   1,280.53/1,921.54 = 540.10/x
3. Step 3: Cross multiply
   1,280.53x = 1,921.54 × 540.10
4. Step 4: Simplify right side
   1,280.53x = 1,037,814.15
5. Step 5: Solve for x
   x = 1,037,814.15/1,280.53
6. Step 6: Final answer
   x = 810.46