Finding the Fourth Proportional to 1,118.02, 1,542.90 and 645.94

Step by Step Solution

1. Step 1: Write the proportion equation
   1,118.02 : 1,542.90 = 645.94 : x
2. Step 2: Convert to fraction form
   1,118.02/1,542.90 = 645.94/x
3. Step 3: Cross multiply
   1,118.02x = 1,542.90 × 645.94
4. Step 4: Simplify right side
   1,118.02x = 996,620.83
5. Step 5: Solve for x
   x = 996,620.83/1,118.02
6. Step 6: Final answer
   x = 891.42