Finding the Fourth Proportional to 1,005.34, 1,387.40 and 563.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,005.34 : 1,387.40 = 563.30 : x
2. Step 2: Convert to fraction form
   1,005.34/1,387.40 = 563.30/x
3. Step 3: Cross multiply
   1,005.34x = 1,387.40 × 563.30
4. Step 4: Simplify right side
   1,005.34x = 781,522.42
5. Step 5: Solve for x
   x = 781,522.42/1,005.34
6. Step 6: Final answer
   x = 777.37