Finding the Fourth Proportional to 1,100.17, 1,648.90 and 612.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,100.17 : 1,648.90 = 612.55 : x
2. Step 2: Convert to fraction form
   1,100.17/1,648.90 = 612.55/x
3. Step 3: Cross multiply
   1,100.17x = 1,648.90 × 612.55
4. Step 4: Simplify right side
   1,100.17x = 1,010,033.70
5. Step 5: Solve for x
   x = 1,010,033.70/1,100.17
6. Step 6: Final answer
   x = 918.07