Finding the Fourth Proportional to 1,205.78, 1,663.89 and 674.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,205.78 : 1,663.89 = 674.61 : x
2. Step 2: Convert to fraction form
   1,205.78/1,663.89 = 674.61/x
3. Step 3: Cross multiply
   1,205.78x = 1,663.89 × 674.61
4. Step 4: Simplify right side
   1,205.78x = 1,122,476.83
5. Step 5: Solve for x
   x = 1,122,476.83/1,205.78
6. Step 6: Final answer
   x = 930.92