Finding the Fourth Proportional to 1,101.96, 1,520.71 and 660.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,101.96 : 1,520.71 = 660.15 : x
2. Step 2: Convert to fraction form
   1,101.96/1,520.71 = 660.15/x
3. Step 3: Cross multiply
   1,101.96x = 1,520.71 × 660.15
4. Step 4: Simplify right side
   1,101.96x = 1,003,895.06
5. Step 5: Solve for x
   x = 1,003,895.06/1,101.96
6. Step 6: Final answer
   x = 911.01