Finding the Fourth Proportional to 1,019.32, 1,406.64 and 553.57

Step by Step Solution

1. Step 1: Write the proportion equation
   1,019.32 : 1,406.64 = 553.57 : x
2. Step 2: Convert to fraction form
   1,019.32/1,406.64 = 553.57/x
3. Step 3: Cross multiply
   1,019.32x = 1,406.64 × 553.57
4. Step 4: Simplify right side
   1,019.32x = 778,673.70
5. Step 5: Solve for x
   x = 778,673.70/1,019.32
6. Step 6: Final answer
   x = 763.91