Finding the Fourth Proportional to 1,021.56, 1,410.24 and 648.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,021.56 : 1,410.24 = 648.72 : x
2. Step 2: Convert to fraction form
   1,021.56/1,410.24 = 648.72/x
3. Step 3: Cross multiply
   1,021.56x = 1,410.24 × 648.72
4. Step 4: Simplify right side
   1,021.56x = 914,850.89
5. Step 5: Solve for x
   x = 914,850.89/1,021.56
6. Step 6: Final answer
   x = 895.54