Finding the Fourth Proportional to 1,006.56, 1,388.72 and 613.44

Step by Step Solution

1. Step 1: Write the proportion equation
   1,006.56 : 1,388.72 = 613.44 : x
2. Step 2: Convert to fraction form
   1,006.56/1,388.72 = 613.44/x
3. Step 3: Cross multiply
   1,006.56x = 1,388.72 × 613.44
4. Step 4: Simplify right side
   1,006.56x = 851,896.40
5. Step 5: Solve for x
   x = 851,896.40/1,006.56
6. Step 6: Final answer
   x = 846.34