Finding the Fourth Proportional to 1,180.77, 1,770.37 and 660.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,180.77 : 1,770.37 = 660.82 : x
2. Step 2: Convert to fraction form
   1,180.77/1,770.37 = 660.82/x
3. Step 3: Cross multiply
   1,180.77x = 1,770.37 × 660.82
4. Step 4: Simplify right side
   1,180.77x = 1,169,895.90
5. Step 5: Solve for x
   x = 1,169,895.90/1,180.77
6. Step 6: Final answer
   x = 990.79