Finding the Fourth Proportional to 1,111.20, 1,533.78 and 668.94

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.20 : 1,533.78 = 668.94 : x
2. Step 2: Convert to fraction form
   1,111.20/1,533.78 = 668.94/x
3. Step 3: Cross multiply
   1,111.20x = 1,533.78 × 668.94
4. Step 4: Simplify right side
   1,111.20x = 1,026,006.79
5. Step 5: Solve for x
   x = 1,026,006.79/1,111.20
6. Step 6: Final answer
   x = 923.33