Finding the Fourth Proportional to 1,019.25, 1,406.57 and 553.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,019.25 : 1,406.57 = 553.50 : x
2. Step 2: Convert to fraction form
   1,019.25/1,406.57 = 553.50/x
3. Step 3: Cross multiply
   1,019.25x = 1,406.57 × 553.50
4. Step 4: Simplify right side
   1,019.25x = 778,533.73
5. Step 5: Solve for x
   x = 778,533.73/1,019.25
6. Step 6: Final answer
   x = 763.83