Finding the Fourth Proportional to 1,019.07, 1,406.31 and 553.32

Step by Step Solution

1. Step 1: Write the proportion equation
   1,019.07 : 1,406.31 = 553.32 : x
2. Step 2: Convert to fraction form
   1,019.07/1,406.31 = 553.32/x
3. Step 3: Cross multiply
   1,019.07x = 1,406.31 × 553.32
4. Step 4: Simplify right side
   1,019.07x = 778,139.45
5. Step 5: Solve for x
   x = 778,139.45/1,019.07
6. Step 6: Final answer
   x = 763.58