Finding the Fourth Proportional to 1,019.38, 1,406.74 and 553.62

Step by Step Solution

1. Step 1: Write the proportion equation
   1,019.38 : 1,406.74 = 553.62 : x
2. Step 2: Convert to fraction form
   1,019.38/1,406.74 = 553.62/x
3. Step 3: Cross multiply
   1,019.38x = 1,406.74 × 553.62
4. Step 4: Simplify right side
   1,019.38x = 778,799.40
5. Step 5: Solve for x
   x = 778,799.40/1,019.38
6. Step 6: Final answer
   x = 763.99