Finding the Fourth Proportional to 1,018.53, 1,405.58 and 552.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,018.53 : 1,405.58 = 552.78 : x
2. Step 2: Convert to fraction form
   1,018.53/1,405.58 = 552.78/x
3. Step 3: Cross multiply
   1,018.53x = 1,405.58 × 552.78
4. Step 4: Simplify right side
   1,018.53x = 776,976.51
5. Step 5: Solve for x
   x = 776,976.51/1,018.53
6. Step 6: Final answer
   x = 762.84