Finding the Fourth Proportional to 1,003.31, 1,384.52 and 555.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,003.31 : 1,384.52 = 555.15 : x
2. Step 2: Convert to fraction form
   1,003.31/1,384.52 = 555.15/x
3. Step 3: Cross multiply
   1,003.31x = 1,384.52 × 555.15
4. Step 4: Simplify right side
   1,003.31x = 768,617.67
5. Step 5: Solve for x
   x = 768,617.67/1,003.31
6. Step 6: Final answer
   x = 766.09