Finding the Fourth Proportional to 1,019.04, 1,406.28 and 553.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,019.04 : 1,406.28 = 553.28 : x
2. Step 2: Convert to fraction form
   1,019.04/1,406.28 = 553.28/x
3. Step 3: Cross multiply
   1,019.04x = 1,406.28 × 553.28
4. Step 4: Simplify right side
   1,019.04x = 778,066.60
5. Step 5: Solve for x
   x = 778,066.60/1,019.04
6. Step 6: Final answer
   x = 763.53