Finding the Fourth Proportional to 1,072.78, 1,480.41 and 658.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,072.78 : 1,480.41 = 658.78 : x
2. Step 2: Convert to fraction form
   1,072.78/1,480.41 = 658.78/x
3. Step 3: Cross multiply
   1,072.78x = 1,480.41 × 658.78
4. Step 4: Simplify right side
   1,072.78x = 975,264.50
5. Step 5: Solve for x
   x = 975,264.50/1,072.78
6. Step 6: Final answer
   x = 909.10