Finding the Fourth Proportional to 1,002.72, 1,382.48 and 648.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,002.72 : 1,382.48 = 648.05 : x
2. Step 2: Convert to fraction form
   1,002.72/1,382.48 = 648.05/x
3. Step 3: Cross multiply
   1,002.72x = 1,382.48 × 648.05
4. Step 4: Simplify right side
   1,002.72x = 895,906.01
5. Step 5: Solve for x
   x = 895,906.01/1,002.72
6. Step 6: Final answer
   x = 893.48