Finding the Fourth Proportional to 1,144.78, 1,579.69 and 647.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,144.78 : 1,579.69 = 647.30 : x
2. Step 2: Convert to fraction form
   1,144.78/1,579.69 = 647.30/x
3. Step 3: Cross multiply
   1,144.78x = 1,579.69 × 647.30
4. Step 4: Simplify right side
   1,144.78x = 1,022,533.34
5. Step 5: Solve for x
   x = 1,022,533.34/1,144.78
6. Step 6: Final answer
   x = 893.21