Finding the Fourth Proportional to 1,111.30, 1,666.83 and 648.79

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.30 : 1,666.83 = 648.79 : x
2. Step 2: Convert to fraction form
   1,111.30/1,666.83 = 648.79/x
3. Step 3: Cross multiply
   1,111.30x = 1,666.83 × 648.79
4. Step 4: Simplify right side
   1,111.30x = 1,081,420.90
5. Step 5: Solve for x
   x = 1,081,420.90/1,111.30
6. Step 6: Final answer
   x = 973.12